Oligonucleotides antisense to rat pituitary tumor transforming gene carboxy-terminal (PTTG-C) and methods of use thereof to inhibit neoplastic cellular proliferation and/or transformation

ABSTRACT

Disclosed is a method of inhibiting neoplastic cellular proliferation and/or transformation of mammalian cells, including cells of human origin, in vitro or in vivo. The inventive method involves the delivery of polynucleotides antisense to PTTG-C-related polynucleotides to mammalian cells, whether in vitro or in vivo, to inhibit the endogenous expression of PTTG. Also disclosed are compositions comprising antisense PTTG carboxy-terminal-related polynucleotides, including compositions comprising expression vectors containing the PTTG-C-related polynucleotides. Kits comprising the inventive compositions are also disclosed for the treatment of neoplastic cellular proliferation in vitro or in vivo.

[0001] This application is a division of U.S. Non-provisionalapplication Ser. No. 09/569,956, filed on May 12, 2000, which is acontinuation-in-part of U.S. Ser. No. 08/894,251, filed on Jul. 23,1999, as a national stage application, under 35 U.S.C. §371, ofinternational application PCT/US97/21463, filed Nov. 21, 1997, whichclaims the priority of the filing date of U.S. Provisional ApplicationSerial No. 60/031,338, filed Nov. 21, 1996. claims the benefit of U.S.Provisional Application No. 60/065,825, filed on Nov. 14, 1997. Thisapplication is also related to U.S. Ser. No. 10/136,056, filed on Apr.29, 2002, U.S. Ser. No. 10/136,082, filed on Apr. 29, 2002, U.S. Ser.No. 10/136,098, filed on Apr. 29, 2002, and U.S. Ser. No. 10/135,671,filed on Apr. 29, 2002, which are all divisions of U.S. Ser. No.09/569,956.

[0002] The U.S. Government has a paid-up license in this invention andthe right in limited circumstances to require the patent owner tolicense others on reasonable terms as provided for by the terms ofContract CA75979, awarded by the National Cancer Institute of theNational Institutes of Health.

BACKGROUND OF THE INVENTION

[0003] Throughout the application various publications are referenced inparentheses. The disclosures of these publications in their entiretiesare hereby incorporated by reference in the application in order to morefully describe the state of the art to which this invention pertains.

[0004] 1. Field of the Invention

[0005] The present invention relates to a method of inhibitingneoplastic cellular proliferation and/or transformation of mammaliancells, in vitro and in vivo.

[0006] 2. Related Art

[0007] Neoplasms, including cancers and other tumors, are the secondmost prevalent cause of death in the United States, causing 450,000deaths per year. One in three Americans will develop cancer, and one infive will die of cancer (Scientific American Medicine, part 12, I, 1,section dated 1987). While substantial progress has been made inidentifying some of the likely environmental and hereditary causes ofcancer, the statistics for the cancer death rate indicates a need forsubstantial improvement in the therapy for cancer and related diseasesand disorders.

[0008] A number of cancer genes, i.e., genes that have been implicatedin the etiology of cancer, have been identified in connection withhereditary forms of cancer and in a large number of well-studied tumorcells. Studies of cancer genes have helped provide some understanding ofthe process of tumorigenesis. While a great deal more remains to belearned about cancer genes, the presently known cancer genes serve asuseful models for understanding tumorigenesis.

[0009] Cancer genes are broadly classified into “oncogenes” which, whenactivated, promote tumorigenesis, and “tumor suppressor genes” which,when damaged, fail to suppress tumorigenesis. While theseclassifications provide a useful method for conceptualizingtumorigenesis, it is also possible that a particular gene may playdiffering roles depending upon the particular allelic form of that gene,its regulatory elements, the genetic background and the tissueenvironment in which it is operating.

[0010] More than 100 oncogenes have been discovered, but only a smallpercentage appear mutated in tumors. (Bishop, J. M., Molecular themes inoncogenesis, Cell 64:235-248 [1991]; Sager, R., Expression genetics incancer: shifting the focus from DNA to XNA, Proc. Natl. Acad Sci.94:952-955 [1997]). Most cancer-related genes exhibit altered expressionpatterns (increasing or decreasing), causing phenotypic changesinvolving signal transduction, cell proliferation, DNA repair,angiogenesis, and apoptosis. (Pawson, T., and Hunter, T., Signaltransduction and growth control in normal and cancer cells, Curr. OpinGene Dev. 4:1-4 [1994]; Bartek, J., et al., Defects in cell cyclecontrol and cancer, J Pathol, 187.95-99 [1999]; Sancer, A., Mechanismsof DNA excision repair, Science 266:1954-1956 [1994]; Hanahan, D., andFolkman, J., Pattern and emerging mechanisms of the angiogenic switchduring tumorigenesis, Cell 86:353-346 [1996]; Wyllie, A H., The geneticregulation of apoptosis, Curr, Opin. Gene Dev. 5:97-104 [1995]).Identifying specific regulators modulating oncogene expression isimportant to provide the basis for development of potential subcellulartherapeutic strategies. (Gibbs, J. B., and Oliff A., Pharmaceuticalresearch in molecular oncology, Cell 79: 193-198 [1994]; Levitzki A.,Signal-transduction therapy: a novel approach to disease management,Eur. J. Biochem. 226:1-13 [1994]).

[0011] Tumor suppressor genes play a role in regulating oncogenesis.Tumor suppressor genes are genes that in their wild-type alleles,express proteins that suppress abnormal cellular proliferation. When thegene coding for a tumor suppressor protein is mutated or deleted, theresulting mutant protein or the complete lack of tumor suppressorprotein expression may fail to correctly regulate cellularproliferation, and abnormal cellular proliferation may take place,particularly if there is already existing damage to the cellularregulatory mechanism. A number of well-studied human tumors and tumorcell lines have been shown to have missing or nonfunctional tumorsuppressor genes. Examples of tumor suppressor genes include, but arenot limited to the retinoblastoma susceptibility gene or RB gene, thep53 gene, the deleted in colon carcinoma (DDC) gene and theneurofibromatosis type 1 (NF-1) tumor suppressor gene (Weinberg, R. A.,Science,254:1138-46 [1991]). Loss of function or inactivation of tumorsuppressor genes may play a central role in the initiation and/orprogression of a significant number of human cancers.

[0012] Anterior pituitary tumors are mostly benign hormone-secreting ornon-functioning adenomas arising from a monoclonal expansion of agenetically mutated pituitary epithelial cell. Pathogenesis of tumorformation in the anterior pituitary has been intensively studied.Mechanisms for pituitary tumorigenesis involve a multi-step cascade ofrecently characterized molecular events. The most well characterizedoncogene in pituitary tumors is gsp; a constitutively activated G(s)αprotein results from certain point mutations ingsp. (E.g., Fragoso, M.C., et al., Activating mutation of the stimulatory G protein [gsp] as aputative cause of ovarian and testicular human stromal Leydig celltumors, J. Clin. Endocrinol. 83(6):2074-78 [1999]; Barlier, A. et al.,Impact of gsp oncogene on the expression of genes coding for Gsalpha,Pit-1, Gi2alpha, and somatostatin receptor 2 in human somatotrophadenomas: involvement of octreotide sensitivity, J. Clin. Endocrinol.Metab. 84(8):2759-65 [1999]; Ballare, E., et al., Activating mutationsof the Gs alpha gene are associated with low levels of Gs alpha proteinin growth hormone-secreting tumors, J. Clin. Endocrinol. Metab.83(12):4386-90 [1999])

[0013] G(s)α mutations occur in about 40% of growth hormone(GH)-secreting tumors, and constitutively activated CREB transcriptionfactor is also found in a subset of these tumors. Although theimportance of GSa mutant proteins in the development of growth-hormonesecreting pituitary tumors is well established, only about one third ofthese tumors contains these mutations, indicating the presence ofadditional transforming events in pituitary tumorigenesis. Althoughpoint mutations of Ras oncogene, loss of heterozygosity (LOH) near theRb locus on chromosome 13, and LOH on chromosome 11 have been implicatedin some pituitary tumors, the mechanism that causes pituitary celltransformation remains largely unknown.

[0014] Recently, a novel pituitary tumor transforming gene, PTTG(previously known as pituitary-tumor-specific-gene [PTSG]), wasisolated. PTTG encodes a securin protein the expression of which causescell transformation, induces the production of basic fibroblast growthfactor (bFGF), is regulated in vitro and in vivo by estrogen, andinhibits chromatid separation. (Pei, L., and Melmed S., Isolation andcharacterization of a pituitary tumor transforming gene, Mol.Endocrinol. 11:433-441 [1997]; Zhang, X., et al., Structure, expression,and function of human pituitary tumor-transforming gene (PTTG), Mol.Endocrinol. 13:156-166 [1999a]; Heaney, A. P., et al., Early involvementof estrogen-induced pituitary tumor transforming gene and fibroblastgrowth factor expression in prolactinoma pathogenesis, Nature Med.5:1317-1321 [1999]; Zou, H., et al., Identification of a vertebratesister-chromatid separation inhibitor involved in transformation andturnorigenesis, Science 285:418-422 [1999])

[0015] By dysregulating chromatid separation, PTTG overexpression mayalso lead to aneuploidy, i.e., cells having one or a few chromosomesabove or below the normal chromosome number (Zou et al. [1999]). Likemost cancer-related genes, the expression of PTTG is restricted innormal tissues, but PTTG expression is dramatically increased inmalignant human cell lines, pituitary tumors, colon carcinomas andcolorectal tumors (Zhang, X., et al. [1 999a]; Zhang, X., et al.,Pituitary tumor transforming gene (PTTG) expression in pituitaryadenornas, J. Clin. Endocrinol. Metab. 84:761-767 [1999b]; Heaney, A.R., et al., Pituitary tumor transforming gene: a novel marker incolorectal tumors, Lancet [In Press; 2000]).

[0016] The recent discovery of a human PTTG gene 2, which shares highsequence homology with human PTTG1, implying the existence of a PTTGgene family. (Prezant, T. R., et al., An intronless homolog of humanproto-oncogene hPTTG is expressed in pituitary tumors: evidence forhPTTG family, J. Clin. Endocrinol. Metab. 84:1149-1152 [1999]). MurinePTTG shares 66% nucleotide base sequence homology with human PTTGI andalso exhibits transforming ability. (Wang, Z. and Melmed, S.,Characterization of the murine pituitary tumor transforming gone (PTTG)and its promoter, Endocrinology [In Press; 2000]). A proline-rich regionwas identified near the protein C-terminus that is critical for PTTG1'stransforming activity. (Zhang, X., et al. [1999a]), as demonstrated bythe inhibitory effect on in vitro transformation, in vivo tumorigenesis,and transactivation, when point mutations were introduced into theproline-rich region. Proline-rich domains may function as SH3 bindingsites to mediate signal transduction of protein-tyrosine kinase.(Pawson, T., Protein modules and signaling networks, Nature 373:573-580[1995]; Kuriyan, J., and Cowburn, D., Modular peptide recognitiondomains in eukaryotic signaling, Annu, Rev. Biophys. Biomol. Struct.26:259-288 [1997]).

[0017] There remains a need for a therapeutic treatment for neoplasms,such as cancer, that inhibits neoplastic cellular proliferation and/ortransformation associated with PTTG overexpression. This and otherbenefits are provided by the present invention as described herein.

SUMMARY OF THE INVENTION

[0018] The present invention relates to a method of inhibitingneoplastic cellular proliferation and/or transformation of mammaliancells, including cells of human origin, whether in vitro or in vivo. Theinventive method relies on the discovery that the nativecarboxy-terminal portion of the pituitary tumor transforming geneprotein (PTTG) is critical to PTTG protein function and that,surprisingly, pituitary tumor transforming gene carboxy-terminal peptide(PTTG-C) molecules have the ability to downregulate pituitary tumortransforming gene (PTTG) expression and/or PTTG function in a dominantnegative manner. In some embodiments, the invention is directed togene-based treatments that deliver PTTG carboxy-terminal-relatedpolynucleotides to mammalian cells to inhibit the endogenous expressionand function of PTTG. Other embodiments are directed to peptide-basedtreatments that deliver PTTG-C peptides to the cells, which inhibitendogenous PTTG expression and/or PTTG function.

[0019] In particular, useful gene-based embodiments of the method ofinhibiting neoplastic cellular proliferation and/or transformation ofmammalian cells involve delivering to the cell a composition comprisinga PTTG-C-related polynucleotide that includes a base sequence thatdefines a PTTG carboxy-terminal peptide-encoding sequence, or defines adegenerate sequence, or defines a sequence complementary to either ofthese. In accordance with the method, the PTTG carboxy-terminal-relatedpolynucleotide, preferably complexed with a cellular uptake-enhancingagent, is delivered in an amount and under conditions sufficient toenter the cell, thereby inhibiting neoplastic cellular proliferationand/or transformation of the cell.

[0020] Alternatively, useful peptide-based embodiments of the method ofinhibiting neoplastic cellular proliferation and/or transformation of amammalian cell involve delivering to a mammalian cell a compositioncomprising a PTTG carboxy-terminal peptide (PTTG-C), or a biologicallyfunctional fragment thereof, preferably complexed with a cellularuptake-enhancing agent, in an amount and under conditions sufficient toenter the cell, thereby inhibiting neoplastic cellular proliferationand/or transformation.

[0021] Because, PTTG protein further mediates the expression of bFGF, animportant angiogenesis activator, the inventive method of inhibitingneoplastic cellular proliferation and/or transformation, practiced invivo, also encompasses a method of inhibiting tumor angiogenesis.Angiogenesis activators, including bFGF and VEGF, are expressed andsecreted by most human carcinoma cells. (Plate, K. H. et al., Nature359:845-48 [1992]; Schultz-Hector, S. and Haghayegh, S., Cancer Res. 531444-49 [1993]; Yamanaka, Y. et al., Cancer Res. 53:5289-96 [1993];Buensing, S. et al.,Anticancer Res. 15:2331-34 [1995]). The discovery,described herein, that the inventive PTTG-C peptides dramatically reducebFGF production by cancer cells (e.g., HeLa), shows that in accordancewith the inventive method, the inventive PTTG-C peptides can impair newblood vessel growth, which is essential for tumor growth. Thus, themethod of inhibiting tumor angiogenesis further inhibits neoplasticcellular proliferation, in vivo.

[0022] The present invention also relates to compositions useful forinhibiting neoplastic cellular proliferation and/or transformation.These include compositions comprising a PTTG carboxy-terminal peptide orcomprising a chimeric or fusion protein that contains a first PTTGcarboxy-terminal peptide segment and a second cellular uptake-enhancingpeptide segment. The invention also relates to compositions comprising aPTTG carboxy-terminal-related polynucleotide, for example, apolynucleotide encoding a PTTG-C peptide or antisense PTTG-C-relatedoligonucleotides. Also included in the invention are compositionscomprising expression vectors containing the PTTG-C-relatedpolynucleotides, including nucleic acids encoding PTTG-C peptides. Theinventive PTTG-C peptides and inventive PTTG-C-related polynucleotidesare useful in the manufacture of pharmaceutical compositions,medicaments or medicants for inhibiting neoplastic cellularproliferation and/or transformation, which contain the inventive PTTG-Cpeptides and PTTG-C-related polynucleotides.

[0023] In accordance with the present invention, there are also providedPTTG carboxy-terminal (PTTG-C) peptides and PTTG-C-relatedpolynucleotides, which can also be isolated from other cellularcomponents The inventive PTTG-C peptides are useful in bioassays, asimmunogens for producing anti-PTTG antibodies, or in therapeuticcompositions containing such peptides and/or antibodies. Also providedare transgenic non-human mammals that comprise mammalian cells thatcomprise embodiments of the inventive PTTG-C-related polynucleotides andexpress the inventive PTTG-C peptides.

[0024] Also provided are antibodies that are specifically immunoreactivewith PTTG proteins, or more particularly, with PTTG-C peptides. Theinventive antibodies specifically bind to PTTG-C peptides. Theseanti-PTTG-C-specific antibodies are useful in assays to determine levelsof PTTG proteins or PTTG-C peptides present in a given sample, e.g.,tissue samples, biological fluids, Western blots, and the like. Theantibodies can also be used to purify PTTG proteins or PTTG-C peptidesfrom crude cell extracts and the like. Moreover, these antibodies areconsidered therapeutically useful to counteract or supplement thebiological effect of PTTG proteins in vivo.

[0025] The present invention is further described by relatedapplications U.S. Ser. No. 09/569,956, filed May 12, 2000, U.S. Ser. No.08/894,251, filed Jul. 23, 1999, international applicationPCT/US97/21463, filed November21, 1997, and U.S. provisional applicationNo. 60/031,338, filed Nov. 21, 1996, the disclosures and drawings ofwhich are incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026]FIG. 1 illustrates transcriptional activation in transfected NIH3T3 cells, as mediated by pGAL4, pGAL4-VP 16, pGAL4-wtPTTG, orpGAL4-mutPTTG 48 hours after transfection. Cell lysate proteins wereassayed for luciferase and β-gal expression. pGAL4 was used as anegative control and pGAL4-VP16 as a positive control.

[0027]FIG. 2 shows PTTG-C and PTTG-Cpm expression in transfected tumorcells. FIG. 2A illustrates expression construct which express aC-terminal peptide of human PTTG protein (PTTGC), corresponding to aminoacid residues 147-202 of SEQ. ID. NO.:4 (i.e., SEQ. ID. NO.:9), underthe control of the CMV promoter (black bar). PXXP represents theproline-rich region(s) of the PTTG-C. A mutant expression vector(PTTG-Cpm), contained point mutations P163A, S165Q, P166L, P170L, P172A,and P173L. FIG. 2B includes representative 1% agarose gels of RT-PCRproducts of HeLa (top panel), T-47D (middle panel), and MCF-7 cells(bottom panel),showing PTTG-C and PTTG-Cpm expression. Products fromreverse transcription carried out in the presence (+) or absence (−) ofRT were used as template in PCR reactions. FIG. 2C shows arepresentative sequencing gel from RT-PCR followed by direct sequencinganalysis showing PTTG-C and PTTG-Cpm expression in respectivetransfectants. Arrows point to nucleotide changes.

[0028]FIG. 3 shows colony formation of HeLa (top row), T-47D (middlerow), and MCF-7 (bottom row) cells transfected with PTTG-C or PTTG-Cpmexpression vectors on soft agar. “Vector” (left column) shows cellstransfected with vector pCI-neo alone, “PTTG-C” (middle column) showscells transfected with vector pCI-neo containing PTTG C-terminalencoding cDNA; “PTTG-Cpm” (right column) shows cells transfected withvector pCI-neo containing mutant PTTG C-terminal cDNA (P163A, S165Q,P166L, P170L, P172A, and P 173L).

[0029]FIG. 4 shows suppression of bFGF secretion by HeLa cellsexpressing PTTG-C peptide. The concentration of bFGF in conditionedmedium derived from transfectants cultured for 72 h as measure by ELISA.“Vector” (two left-most bars) indicates medium conditioned by cellstransfected with vector pCI-neo alone; “PTTG-C” (three middle bars)indicates medium conditioned by cells transfected with vector pCI-neocontaining wtPTTG-C-terminal encoding cDNA; “PTTG-Cpm” (three right-mostbars) indicates medium conditioned by transfected with vector pCI-neocontaining mutant PTTG C-terminal encoding cDNA (P163A, S165Q, P166L,P170L, P172A, and P173L).

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

[0030] The present invention relates to a method of inhibitingPTTG-mediated neoplastic cellular proliferation and/or transformation ofa mammalian cell, including but not limited to, a cell of human ornon-human origin. Non-human mammalian cells also originate from, or in,any mammalian animal, e.g., a non-human primate, rat, mouse, rabbit,guinea pig, hamster, bovine, porcine, ovine, equine, canine, feline,pachyderm, and the like. The mammalian cell can be situated in vivo,i.e., within a mammalian animal subject or human subject, or in vitro,i.e., the cell can be a cultured cell.

[0031] For the purposes of the invention, “neoplastic cellularproliferation” includes neoplastic (malignant or benign), hyperplastic,cytologically dysplastic and/or premalignant cellular growth orproliferation in a mammalian subject or cell culture. Hyperplasticcellular growth or proliferation includes abnormal multiplication orincrease in the numbers of normal cells in a normal arrangement in atissue, for example, as is common in benign prostatic hyperplasia.Cytologically dysplastic and/or premalignant cellular growth orproliferation include increases in cellular numbers of karyotypicallyabnormal but non-malignant cells within a tissue. Examples include somebenign prostatic hyperplasias/dysplasia and cervicalhyperplasias/dysplasias.

[0032] Neoplastic cellular growth and/or proliferation, i.e., growth ofabnormally organized tissue, includes malignant and non-malignantneoplasms. Malignant neoplasms include primary, recurrent, and/or ormetastatic cancerous tumors originating in any tissues, for example,carcinomas, sarcomas, lymphomas, mesotheliomas, melanomas, gliomas,nephroblastomas, glioblastomas, oligodendrogliomas, astrocytomas,ependymomas, primitive neuroectodermal tumors, a typical meningiomas,malignant meningiomas, or neuroblastomas, originating in the pituitary,hypothalamus, lung, kidney, adrenal, ureter, bladder, urethra, breast,prostate, testis, skull, brain, spine, thorax, peritoneum, ovary,uterus, stomach, liver, bowel, colon, rectum, bone, lymphatic system,skin, or in any other organ or tissue of the subject.

[0033] In accordance with gene-based embodiments of the method ofinhibiting neoplastic cellular proliferation and/or transformation, aninventive composition is delivered to the cell, which compositioncomprises a PTTG carboxy-terminal-related polynucleotide. A “PTTGcarboxy-terminal-related” polynucleotide is a polynucleotide having acontiguous sequence of bases (e.g., adenine [A], thymine [T], uracil[U], guanine [G], and/or cytosine [C]) defining a sequence specific tothe 3′ coding region of PTTG. The 3′-end or terminal extends fromapproximately the mid-point of a cDNA coding sequence encoding a nativePTTG to its end at a stop codon. The PTTG carboxy-terminal-relatedpolynucleotide can be a sequence encoding a carboxy-terminal portion ofa mammalian PTTG protein (i.e., a PTTG-C peptide), as described morefully below, or encoding a PTTG-specific fragment thereof, or adegenerate coding sequence, or a sequence complementary to any of these.

[0034] In some preferred embodiments, the inventive composition includesa nucleic acid construct, such as a plasmid or viral expression vector,which comprises the polynucleotide in a sense or antisense orientation,and from which PTTG-specific mRNA transcript can be expressed in thecell. In a preferred embodiment, the nucleic acid construct contains apolynucleotide encoding a mammalian PTTG carboxy-terminal (PTTG-C)peptide, which can be any PTTG-C peptide or functional fragment thereofas described herein. The composition can also contain one or more helperplasmids or viruses, if appropriate. The plasmid or viral expressionvector is a nucleic acid construct that includes a promoter regionoperatively linked to the polynucleotide in a transcriptional unit.

[0035] As used herein, a promoter region refers to a segment of DNA thatcontrols transcription of a DNA to which it is operatively linked. Thepromoter region includes specific sequences that are sufficient for RNApolymerase recognition, binding and transcription initiation. Inaddition, the promoter region includes sequences that modulate thisrecognition, binding and transcription initiation activity of RNApolymerase. These sequences may be cis acting or may be responsive totrans acting factors. Promoters, depending upon the nature of theregulation, may be constitutive or regulated. Exemplary promoterscontemplated for use in the practice of the present invention includethe SV40 early promoter, the cytomegalovirus (CMV) promoter, the mousemammary tumor virus (MMTV) steroid-inducible promoter, Moloney murineleukemia virus (MMLV) promoter, and the like.

[0036] As used herein, “expression” refers to the process by whichpolynucleic acids are transcribed into mRNA and translated intopeptides, polypeptides, or proteins. If the polynucleic acid is derivedfrom genomic DNA, expression may, if an appropriate eukaryotic host cellor organism is selected, include splicing of the mRNA.

[0037] As used herein, the term “operatively linked” refers to thefunctional relationship of DNA with regulatory and effector nucleotidesequences, such as promoters, enhancers, transcriptional andtranslational stop sites, and other signal sequences. For example,operative linkage of DNA to a promoter refers to the physical andfunctional relationship between the DNA and the promoter such that thetranscription of such DNA is initiated from the promoter by an RNApolymerase that specifically recognizes, binds to and transcribes theDNA. Thus, “operatively linked” means that, within a transcriptionalunit, the promoter sequence, is located upstream (i.e., 5′ in relationthereto) from the coding sequence and the coding sequence, is 3′ to thepromoter, or alternatively is in a sequence of genes or open readingframes 3′ to the promoter and expression is coordinately regulatedthereby. Both the promoter and coding sequences are oriented in a 5′ to3′ manner, such that transcription can take place in vitro in thepresence of all essential enzymes, transcription factors, co-factors,activators, and reactants, under favorable physical conditions, e.g,suitable pH and temperature. This does not mean that, in any particularcell, conditions will favor transcription. For example, transcriptionfrom a tissue-specific promoter is generally not favored in heterologouscell types from different tissues.

[0038] The term “nucleic acid” encompasses ribonucleic acid (RNA) ordeoxyribonucleic acid (DNA), which DNA can be complementaryDNA (cDNA) orgenomic DNA, e.g. a gene encoding a PTTG protein. “Polynucleotides”encompass nucleic acids containing a “backbone” formed by phosphodiesterlinkages between ribosyl or deoxyribosyl moieties Polynucleotides alsoinclude nucleic acid analogs, for example polynucleotides havingalternative linkages as known in the art. Examples includephosphorothioate linkages (e.g., phosphorothioate oligodeoxynucleotides;S-oligonucleotides), mixed phosphorothioate and phosphodiester linkages(e.g., S-O-oligodeoxynucleotides and phosphodiester/phosphorothioate2′-O-methyl-oligoribonucleotides; Zhou, W. et al., Mixed backboneoligonucleotides as second-generation antisense agents with reducedphosphthioate-related side effects, Bioorg. Med. Chem. Lett.8(22):3269-74 [1998]), methylphosphonate-phosphodiester modifications(MP-O-oligonucleotides; Zhao, Q. et al., Comparison of cellular bindingand uptake of antisense phosphodiester, phosphorothioate, and mixedphosphorothioate and methylphosphonate oligonucleotides, Antisense ResDev. 3(1):53-66 [1993]), or morpholino oligonucleotides (e.g., Schmajuk,G. et al., Antisense oligonucleotides with different backbones.Modification of splicing pathways and efficacy of uptake, J. Biol. Chem.274(31):21783-89 [1999]).

[0039] Also included among useful polynucleotides are nucleic acidanalogs having a pseudopeptide or polyamide backbone comprisingN-(2-aminoethyl)glycine moieties, i.e., peptide nucleic acids (PNA).(E.g., Nielsen, P E., Peptide nucleic acids: on the road to new genetherapeutic drugs, Pharmacol. Toxicol. 86(1):3-7 [2000]; Soomets, U. etal., Antisense properties of peptide nucleic acids, Front. Biosci.4:D782-86 [1999]; Tyler, B. M. et al., Peptide nucleic acids targeted tothe neurotensin receptor and administered i.p. cross the blood-brainbarrier and specifically reduce gene expression, Proc. Natl. Acad. Sci.USA 96(12):7053-58 [1999]).

[0040] Polynucleotides include sense or antisense polynucleotides.“Polynucleotides” also encompasses “oligonucleotides”.

[0041] A polynucleotide sequence complementary to a PTTG-specificpolynucleotide sequence, as used herein, is one binding specificallywith a PTTG-specific nucleotide base sequence. The phrase “bindingspecifically” encompasses the ability of a polynucleotide sequence torecognize a complementary base sequence and to form double-helicalsegments therewith via the formation of hydrogen bonds between thecomplementary base pairs. Thus, a complementary sequence includes, forexample, an antisense sequence with respect to a sense sequence orcoding sequence.

[0042] In some embodiments of the PTTG-C-related polynucleotide, thepolynucleotide is in a sense orientation within the transcriptionalunit, such that mRNA transcript can be produced, which when translatedresults in a translation product, such as a PTTG protein or a PTTGcarboxy-terminal peptide (PTTG-C). In other embodiments, thePTTG-C-related polynucleotide is in an antisense orientation such thattranscription results in a transcript complementary to and hybridizablewith a naturally-occurring sense PTTG mRNA molecule under physiologicalconditions, inhibiting or blocking translation therefrom. Thus,antisense oligonucleotides inactivate target mRNA sequences by eitherbinding thereto and inducing degradation of the mRNA by, for example,RNase I digestion, or inhibiting translation of mRNA target sequence byinterfering with the binding of translation-regulating factors orribosomes, or by inclusion of other chemical structures, such asribozyme sequences or reactive chemical groups which either degrade orchemically modify the target mRNA. For example, an antisenseoligonucleotide targeted to a PTTG carboxy-terminal-relatedpolynucleotide segment of mRNA or genomic DNA is effective in inhibitingexpression of PTTG.

[0043] Gene-based therapy strategies employing antisenseoligonucleotides are well known in the art. (E.g., Rait, A. et al.,3′-End conjugates of minimally phosphorothioate-protectedoligonucleotides with 1-O-hexadecylglycerol: synthesis and anti-rasactivity in radiation-resistant cells, Bioconjug Chem., 11(2):153-60[2000]; Stenton, G. R. et al., Aerosolized syk antisense suppresses sykexpression, mediator release from macrophages, and pulmonaryinflammation, J. Immunol., 164(7):3790-7 [2000]; Suzuki, J. et al.,Antisense Bcl-x oligonucleotide induces apoptosis and prevents arterialneointimal formation in murine cardiac allografts, Cardiovas. Res.,45(3):783-7 [2000]; Kim, J. W. et al., Antisense oligodeoxynucleotide ofglyceraldehyde-3-phosphate dehyrdogenase gene inhibits cellproliferation and induces apoptosis in human cervical carcinoma cellline, Antisense Nucleic Acid Drug Dev., 9(6):507-13 [1999]; Han, D. C.et al., Therapy with antisense TGF-betal oligodeoxynucleotides reduceskidney weight and matrix mRNAs in diabetic mice, Am. J. Physiol. RenalPhysiol., 278(4):F628-F634 [2000]; Scala, S. et al., Adenovirus-mediatedsuppression of HMGI (Y) protein synthesis as potential therapy of humanmalignant neoplasias, Proc. Natl. Acad. Sci. USA, 97(8):4256-4261[2000]; Arteaga, C. L., et al., Tissue-targeted antisense c-fosretroviral vector inhibits established breast cancer xenografts in nudemice, Cancer Res., 56(5):1098-1103 [1996]; Muller, M. et al., Antisensephosphorothloate oligodeoxynucleotide down-regulation of theinsulin-like growth factor I receptor in ovarian cancer cells, Int. J.Cancer, 77(4).567-71 [1998]; Engelhard, H. H., AntisenseOligodeoxynucleotide Technology: Potential Use for the Treatment ofMalignant Brain Tumors, Cancer Control, 5(2):163-170 [1998];Alvarez-Salas, L. M. et al., Growth inhibition of cervical tumor cellsby antisense oligodeoxynucleotides directed to the human papillomavirustype 16 E6 gene, Antisense Nucleic Acid Drug Dev., 9(5):441-50 [1999];Im, S. A., et al., Antiangiogenesis treatment for gliomas: transfer ofantisense-vascular endothelial growth factor inhibits tumor growth invivo, CancerRes.,59(4):895-900 [1999]; Maeshima, Y. et al., Antisenseoligonucleotides to proliferating cell nuclear antigen and Ki-67 inhibithuman mesangial cell proliferation, J. Am. Soc. Nephrol., 7(10):2219-29[1996]; Chen, D. S. et al., Retroviral Vector-mediated transfer of anantisense cyclin G1 construct inhibits osteosarcoma tumor growth in nudemice, Hum. Gene Ther, 8(14): 1667-74 [1997]; Hirao, T. et al., Antisenseepidermal growth factor receptor delivered by adenoviral vector blockstumor growth in human gastric cancer, Cancer Gene Ther. 6(5).423-7[1999], Wang, X. Y. et al., Antisense inhibition of protein kinaseCalpha reverses the transformed phenotype in human lung carcinoma cells,Exp. Cell Res., 250(1):253-63 [1999]; Sacco, M. G. et al., In vitro andin vivo antisense-mediated growth inhibition of a mammary adenocarcinomafrom MMTV-neu transgenic mice, Gene Ther., 5(3);388-93 [1998]; Leonetti,C. et al., Antitumor effect of c-myc antisense phosphorothioateoligodeoxynucleotides on human melanoma cells in vitro and in mice, JNatl. Cancer Inst., 88(7):419-29 [1996]; Laird, A. D. et al., Inhibitionof tumor growth in liver epthelial cells transfected with a transforminggrowth factor alpha antisensegene, Cancer Res. 54(15):4224-32 (Aug. 1,1994); Yazaki, T. et al., Treatment of glioblastoma U-87 by systemicadministration of an antisense protein kinase C-alpha phosphorothioateoligodeoxynucleotide, Mol. Pharmacol., 50(2):236-42 [1996]; Ho, P. T. etal., Antisense oligonucleotides as therapeuticsfor malignant diseases,Semin. Oncol., 24(2): 187-202 [1997]; Muller, M. et al., Antisensephosphorothioate oligodeoxynucleotide down-regulation of theinsulin-like growth factor I receptor in ovarian cancer cells, Int. J.Cancer, 77(4):567-71 [1998]; Elez, R. et al., Polo-like kinasel, a newtarget for antisense tumor therapy, Biochem. Biophys. Res. Commun.,269(2):352-6 [2000]; Monia, B. P. et al., Antitumor activity of aphosphorothioate antisense oligodeoxynucleotide targeted against C-rafkinase, Nat. Med., 2(6).668-75 [1996]).

[0044] In other embodiments of the inventive method, the inventivecomposition comprises a PTTG carboxy-terminal-related polynucleotidethat is not contained in an expression vector, for example, a syntheticanti sense oligonucleotide, such as a phosphorothioateoligodeoxynucleotide. Synthetic antisense oligonucleotides, or otherantisense chemical structures designed to recognize and selectively bindto mRNA, are constructed to be complementary to portions of the PTTGcoding strand, for example, to coding sequences shown in SEQ ID NOS:1,3, 10, 15, 18, or 19 (Tables 1-6 below). By preventing translationalexpression of at least part of the PTTG 3′ coding region, an antisensePTTG carboxy-terminal-related polynucleotide is useful, in accordancewith the inventive method, to prevent expression of PTTG protein that isfunctional in mediating neoplastic cellular proliferation and/ortransformation.

[0045] In preferred embodiments of the method of inhibiting neoplasticcellular proliferation and/or transformation, the composition alsocomprises an uptake-enhancing agent as further described herein.Inventive compositions, containing the uptake-enhancing agent complexedwith a PTTG-specific polynucleotide, are designed to be capable ofpassing through the cell membrane in order to enter the cytoplasm of thecell by virtue of physical and chemical properties. In addition, thecomposition can be designed for delivery only to certain selected cellpopulations by targeting the composition to be recognized by specificcellular uptake mechanisms which take up the PTTG-specificpolynucleotides only within select cell populations. For example, thecomposition can include a receptor agonist to bind to a receptor foundonly in a certain cell type.

[0046] The inventive composition can also optionally contain one or morepharmaceutically acceptable carrier(s). As used herein, the term“acceptable carrier” encompasses any of the standard pharmaceuticalcarriers. The carrier can be an organic or inorganic carrier orexcipient, such as water and emulsions such as an oil/water or water/oilemulsion, and various types of wetting agents. The active ingredient(s)can optionally be compounded in a composition formulated, for example,with non-toxic, pharmaceutically acceptable carriers for infusions,tablets, pellets, capsules, solutions, emulsions, suspensions, and anyother form suitable for use.

[0047] Such carriers also include glucose, lactose, gum acacia, gelatin,mannitol, starch paste, magnesium trisilicate, talc, corn starch,keratin, colloidal silica, potato starch, urea, medium chain lengthtriglycerides, dextrans, normal saline, phosphate buffered saline andother carriers suitable for use in manufacturing preparations, in solid,semisolid, or liquid form. In addition auxiliary, stabilizing,thickening and coloring agents and perfumes can be used as appropriate.

[0048] PTTG-specific polynucleotides, including PTTGcarboxy-terminal-related polynucleotides, are determined by basesequence similarity or homology to known mammalian PTTG-specificnucleotide sequences. Base sequence homology is determined by conductinga base sequence similarity search of a genomics data base, such as theGenBank database of the National Center for Biotechnology Information(NCBI; www.ncbi.nlm.nih.gov/BLAST/), using a computerized algorithm,such as PowerBLAST, QBLAST, PSI-BLAST, PHI-BLAST, gapped or ungappedBLAST, or the “Align” program through the Baylor College of Medicineserver (www.hgsc.bcm.tmc.edu/seq data). (E.g., Altchul, S. F., et al.,Gapped BLAST and PSI-BLAST: a new generation of protein database searchprograms, Nucleic Acids Res. 25(17):3389-402 [1997]; Zhang, J., &Madden, T. L., PowerBLAST: a new network BLAST application forinteractive or automated sequence analysis and annotation, Genome Res.7(6):649-56 [1997]; Madden, T. L., et al., Applications of network BLASTserver, Methods Enzymol. 266:131-41 [1996]; Altschul, S. F., et al.,Basic local alignment search tool, J. Mol. Biol. 215(3):403-10 [1990]).Preferably, a PTTG-specific polynucleotide sequence is at least 5 to 30contiguous nucleotides long, more preferably at least 6 to 15 contiguousnucleotides long, and most preferably at least 7 to 10 contiguousnucleotides long. Preferably, the inventive PTTGcarboxy-terminal-related polynucleotide is at least about 45 contiguousnucleotides long.

[0049] Preferred examples of PTTG-specific coding sequences include thesequence for human PTTG (hPTTG or PTTG1). The PTTG1 peptide is encodedby the open reading frame at nucleotide positions 95 through 700 ofhuman PTTG1 gene sequence SEQ. ID.NO.:3 (Table 1 below). TABLE 1 PTTG1gene sequence. 1 ATGGCCGCGA GTTGTGGTTT AAACCAGGAG TGCCGCGCGT CCGTTCACCG(SEQ. ID. NO.:3) 51 CGGCCTCAGA TGAATGCGGC TGTTAAGACC TGCAATAATCCAGAATGGCT 101 ACTCTGATCT ATGTTGATAA GGAAAATGGA GAACCAGGCA CCCGTGTGGT151 TGCTAAGGAT GGGCTGAAGC TGGGGTCTGG ACCTTCAATC AAAGCCTTAG 201ATGGGAGATC TCAAGTTTCA ACACCACGTT TTGGCAAAAC GTTCGATGCC 251 CCACCAGCCTTACCTAAAGC TACTAGAAAG GCTTTGGGAA CTGTCAACAG 301 AGCTACAGAA AAGTCTGTAAAGACCAAGGG ACCCCTCAAA CAAAAACAGC 351 CAAGCTTTTC TGCCAAAAAG ATGACTGAGAAGACTGTTAA AGCAAAAAGC 401 TCTGTTCCTG CCTCAGATGA TGCCTATCCA GAAATAGAAAAATTCTTTCC 451 CTTCAATCCT CTAGACTTTG AGAGTTTTGA CCTGCCTGAA GAGGACCAGA501 TTGCGCACCT CCCCTTGAGT GGAGTGCCTC TCATGATCCT TGACGAGGAG 551AGAGAGCTTG AAAAGCTGTT TCAGCTGGGC CCCCCTTCAC CTGTGAAGAT 601 GCCCTCTCCACCATGGGAAT CCAATCTGTT GCAGTCTCCT TCAAGCATTC 651 TGTCGACCCT GGATGTTGAATTGCCACCTG TTTGCTGTGA CATAGATATT 701 TAAATTTCTT AGTGCTTCAG AGTTTGTGTGTATTTGTATT AATAAAGCAT 751 TCTTTAACAG ATAAAAAAAA AAAAAAAAA.

[0050] The 3′ coding region of PTTG1 includes the following168-nucleotide sequence, which corresponds to nucleotide positions 533through 700 of SEQ. ID. NO.:3, shown in Table 2 below. TABLE 2 Portionof 3′ coding region of PTTG1 1 ATGATCCTTG ACGAGGAGAG AGAGCTTGAAAAGCTGTTTC AGCTGGGCCC (SEQ ID NO.:10) 51 CCCTTCACCT GTGAAGATGCCCTCTCCACC ATGGGAATCC AATCTGTTGC 101 AGTCTCCTTC AAGCATTCTG TCGACCCTGGATGTTGAATT GCCACCTGTT 151 TGCTGTGACA TAGATATT.

[0051] The 3′ coding region of rat PTTG includes the following168-nucleotide sequence, which corresponds to nucleotide positions 722through 889 of SEQ. ID. NO.:1, shown in Table 4 below. TABLE 4 Portionof 3′ coding region of rat PTTG. ATG ATC CTG AAT GAA GAG AGG GGG CTT GAGAAG GTG GTG GAG CTG GAG 48 (SEQ. ID. NO.:18) CCC GCT TGC CCT CTG GAG AAGGGG TTG GTA GGG TGG GAA TGT GAT GGG 96 TTG GGG TGT GGT GGG AGG GGG GTGTGG GGT GTG GAT GTT GAA TTG GGG 144 GGT GTT TGT TAG GAT GGA GAT ATT. 168

[0052] Another useful example of a PTTG-specific coding sequence is asequence that encodes a murine PTTG peptide, including nucleotidepositions 304 through 891 of SEQ. ID. NO.15 (Table 5 below). TABLE 5Murine PTTG sequence. 1 TCTTGAACTT GTTATGTAGC AGGAGGCCAA ATTTGAGCATCCTCTTGGCT TCTCTTTATA (SEQ. ID. NO.:15) 61 GCAGAGATTG TAGGCTGGAGACAGTTTTGA TGGGTGCCAA CATAAACTGA TTTCTGTAAG 121 AGTTGAGTGT TTTATGACCCTGGCGTGCAG ATTTAGGATC TGGATTAAGC CTGTTGACTT 181 CTCCAGCTAC TTATAAATTTTTGTGCATAG GTGCCCTGGG TAAAGCTTGG TCTCTGTTAC 241 TGCGTAGTTT TTCCAGCCGTCTCAATGCCA ATATTCAGGC TCTCTCCCTT AGAGTAATCC 301 AGAATGGCTA CTCTTATCTTTGTTGATAAG GATAATGAAG AACCCGGCCG CCGTTTGGCA 361 TCTAAGGATG GGTTGAAGCTGGGCACTGGT GTCAAGGCCT TAGATGGGAA ATTGCAGGTT 421 TCAACGCCTC GAGTCGGCAAAGTGTTCAAT GCTCCAGCCG TGCCTAAAGC CAGCAGAAAG 481 GCTTTGGGGA CAGTCAACAGAGTTGCCGAA AAGCCTATGA AGACTGGCAA ACCCCTCCAA 541 CCAAAACAGC CGACCTTGACTGGGAAAAAG ATCACCGAGA AGTCTACTAA GACACAAAGC 601 TCTGTTCCTG CTCCTGATGATGCCTACCCA GAAATAGAAA AGTTCTTCCC TTTCAATCCT 661 CTAGATTTTG ACCTGCCTGAGGAGCACCAG ATCTCACTTC TCCCCTTGAA TGGCGTGCCT 721 CTCATCACCC TGAATGAAGAGAGAGGGCTG GAGAAGCTGC TGCATCTGGG CCCCCCTAGC 781 CCTCTGAAGA CACCCTTTCTATCATGGGAA TCTGATCCGC TGTACTCTCC TCCCAGTGCC 841 CTCTCCACTC TGGATGTTGAATTGCCGCCT GTTTGTTACG ATGCAGATAT TTAAACTTCT 901 TACTTCTTTG TAGTTTCTGTATGTATGTTG TATTAATAAA GCATT

[0053] The 3′ coding region of murine PTTG includes the following168-nucleotide sequence, which corresponds to nucleotide positions 724through 891 of SEQ. ID. NO.:15, shown in Table 6 below. TABLE 6 Portionof 3′ coding region of murine PTTG. ATCACCCTGA ATGAAGAGAG AGGGCTGGAGAAGCTGCTGC ATCTGGGCCC CCCTAGCCCT 60 (SEQ ID NO 19) CTGAAGACAC CCTTTCTATCATGGGAATCT GATCCGCTGT ACTCTCCTCC CAGTGCCCTC 120 TCCACTCTGG ATGTTGAATTGCCGCCTGTT TGTTACGATG CAGATATT. 168

[0054] Inventive PTTG-C-related polynucleotides having nucleotidessequences of SEQ. ID.NOS.:10, 18, or 19, degenerate coding sequences, orsequences complementary to any of these, are merely illustrative ofuseful PTTG carboxy-terminal-related polynucleotides. Other useful PTTGcarboxy-terminal-related polynucleotides are functional fragments of anyof SEQ. ID. NOS.:10, 18, or 19 at least about 45 contiguous nucleotideslong, degenerate coding sequences, or sequences complementary to any ofthese, the presence of which in the cell can function to downregulateendogenous PTTG expression and/or PTTG function, which functionality canbe determined by routine screening.

[0055] As used herein, the term “degenerate” refers to codons thatdiffer in at least one nucleotide from a reference nucleic acid, e.g.,SEQ ID NOS:1, 3, 10, 15, 18, or 19, but encode the same amino acids asthe reference nucleic acid. For example, codons specified by thetriplets “UCU”, “UCC”, “UCA”, and “UCG” are degenerate with respect toeach other since all four of these codons encode the amino acid serine.

[0056] Other useful polynucleotides include nucleic acids or otherpolynucleotides, that differ in sequence from the sequences shown in SEQID NO:1, SEQ. ID. NO.:3, SEQ. ID. NO.:10, SEQ. ID. NO.:15, SEQ. ID.NO.:18, and SEQ. ID. NO.:19, but which when expressed in a cell, resultin the same phenotype. Phenotypically similar nucleic acids are alsoreferred to as “functionally equivalent nucleic acids”. As used herein,the phrase “functionally equivalent nucleic acids” encompasses nucleicacids characterized by slight and non-consequential sequence variationsthat will function in substantially the same manner, compared to any ofthe detailed nucleotide sequences disclosed herein, to produce PTTGprotein functional with respect to inducing neoplastic cellularproliferation and/or transformation, or PTTG-C peptide(s) functionalwith respect to inhibition of neoplastic cellular proliferation and/ortransformation, and/or polypeptide products functional with respect toimmunogenicity. Such polynucleotides can have substantially the samecoding sequences as the reference sequences, encoding the amino acidsequence as set forth in SEQ. ID. NO.:2, SEQ. ID. NO.:4, SEQ.11). NO.:9,SEQ. ID. NO:14, SEQ. ID. NO.:16, or SEQ. ID. NO.:17 or a larger aminoacid sequence including SEQ. ID. NO.:2, SEQ. ID. NO.:4, SEQ. ID. NO.:9,SEQ. ID. NO.14, SEQ. ID. NO.:16, or SEQ. ID. NO.:17. As employed herein,the term “substantially the same nucleotide sequence” refers to DNAhaving sufficient identity to the reference polynucleotide, such that itwill hybridize to the reference nucleotide under moderately stringenthybridization conditions. In other embodiments, DNA having“substantially the same nucleotide sequence” as the reference nucleotidesequence has at least about 60% identity with respect to the referencenucleotide sequence. DNA having at least 70%, more preferably at least90%, yet more preferably at least 95%, identity to the referencenucleotide sequence is preferred.

[0057] In preferred embodiments, functionally equivalent nucleic acidsencode polypeptides or peptide fragments that are the same as thosedisclosed herein or that have conservative amino acid variations, orthat encode larger polypeptides that include SEQ. ID. NO.:2, SEQ. ID.NO.:4, SEQ. ID. NO.:9, or SEQ. ID. NO.:14, SEQ. ID. NO.:16, or SEQ. ID.NO.:17, or fragments of any of these that are biologically functionalfragments with respect to inhibiting neoplastic cellular proliferationand/or transformation. For example, conservative variations includesubstitution of a non-polar residue with another non-polar residue, orsubstitution of a charged residue with a similarly charged residue.These variations include those recognized by skilled artisans as thosethat do not substantially alter the tertiary structure of the protein.

[0058] Useful polynucleotides can be produced by a variety of methodswell-known in the art, e.g., by employing PCR and other similaramplification techniques, using oligonucleotide primers specific tovarious regions of SEQ ID NOS:1, 3, 10, 15, 18, 19, or functionallyequivalent polynucleotide sequences. Other synthetic methods forproducing polynucleotides or oligonucleotides of various lengths arealso well known.

[0059] In accordance with the method, preferred polynucleotideshybridize under moderately stringent, preferably high stringency,conditions to substantially the entire sequence, or substantial portions(i.e., typically at least 15-30 nucleotide) of the nucleic acid sequenceset forth in SEQ ID NOS:1, 3, 10, 15, 18, or 19, or to complementarysequences.

[0060] The phrase “stringent hybridization” is used herein to refer toconditions under which annealed hybrids, or at least partially annealedhybrids, of polynucleic acids or other polynucleotides are stable. Asknown to those of skill in the art, the stability of hybrids isreflected in the melting temperature (Tm) of the hybrids. In general,the stability of a hybrid is a function of sodium ion concentration andtemperature. Typically, the hybridization reaction is performed underconditions of relatively low stringency, followed by washes of varying,but higher, stringency. Reference to hybridization stringency relates tosuch washing conditions.

[0061] As used herein, the phrase “moderately stringent hybridization”refers to conditions that permit target-DNA to bind a complementarynucleic acid that has about 60% sequence identity or homology,preferably about 75% identity, more preferably about 85% identity to thetarget DNA; with greater than about 90% identity to target-DNA beingespecially preferred. Preferably, moderately stringent conditions areconditions equivalent to hybridization in 50% formamide, 5×Denhart'ssolution, 5×SSPE, 0.2% SDS at 42° C., followed by washing in 0.2×SSPE,0.2% SDS, at 65° C.

[0062] The phrase “high stringency hybridization” refers to conditionsthat permit hybridization of only those nucleic acid sequences that formstable hybrids in 0.018 M NaCl at 65° C. (i.e., if a hybrid is notstable in 0.018 M NaCl at 65° C., it will not be stable under highstringency conditions, as contemplated herein). High stringencyconditions can be provided, for example, by hybridization in 50%formamide, 5×Denhart's solution, 5×SSPE, 0.2% SDS at 42° C., followed bywashing in 0.1×SSPE, and 0.1% SDS at 65° C.

[0063] The phrase “low stringency hybridization” refers to conditionsequivalent to hybridization in 10% formamide, 5×Denhart's solution,6×SSPE, 0.2% SDS at 42° C., followed by washing in 1×SSPE, 0.2% SDS, at50° C. Denhart's solution and SSPE (see, e.g., Sambrook et al.,Molecular Cloning, A Laboratory Manual, Cold Spring Harbor LaboratoryPress [1989]) are well known to those of skill in the art as are othersuitable hybridization buffers.

[0064] The PTTG carboxy-terminal-related polynucleotide can be, but isnot necessarily, of homologous origin with respect to the cell, due tothe relatively high degree of sequence homology among mammalian PTTGsequences. PTTG carboxy-terminal-related polynucleotides of heterologousmammalian origin with respect to the cell is also useful. Thus, forexample, in accordance with the inventive method, a humanPTTG-C-encoding sequence functions to down regulate endogenous PTTGexpression and/or PTTG function in cells of non-human mammalian origin,such as murine or rat cells, and vice versa. In preferred embodiments ofthe method of inhibiting neoplastic cellular proliferation and/ortransformation of a mammalian cell, the polynucleotide is complexed witha cellular uptake-enhancing agent, in an amount and under conditionssufficient to enter the cell. An “uptake-enhancing” agent, as utilizedherein, means a composition of matter for enhancing the uptake ofexogenous polynucleotides, such as DNA segment(s), nucleic acid analogs,or nucleic acid constructs, into a eukaryotic cell, preferably amammalian cell, and more preferably a human cell. The enhancement ismeasured relative to the polynucleotide uptake in the absence of theuptake-enhancing agent, in the process of transfecting or transducingthe cell. Complexation with uptake-enhancing agent(s) generally augmentsthe uptake of a polynucleotide into the cell and/or reduces itsbreakdown by nucleases during its passage through the cytoplasm.

[0065] In accordance with preferred embodiments of the inventive method,PTTG carboxy-terminal-related polynucleotides or PTTG-C peptides arecomplexed with an uptake-enhancing agent. “Complexed” means that thepolynucleotide or peptide is a constituent or member of a complex,mixture, or adduct resulting from chemical binding or bonding betweenand/or among the other constituents, including the cellularuptake-enhancing agent(s), and/or their moieties. Chemical binding orbonding can have the nature of a covalent bond, ionic bond, hydrogenbond, hydrophobic bond, or any combination of these bonding typeslinking the constituents of the complex at any of their parts ormoieties, of which a constituent can have one or a multiplicity ofmoieties of various sorts. Not every constituent of a complex need bebound to every other constituent, but each constituent has at least onechemical bond with at least one other constituent of the complex.Constituents can include, but are not limited to, molecular compounds ofa polar, non-polar, or detergent character; ions, including cations,such as, but not limited to, Na⁺, K⁺, Li⁺, Ca²⁺, Mg²⁺, Fe²⁺, Fe³⁺, Zn²⁺,Cu⁺, Cu²⁺, and/or NH⁴⁺, or anions, such as, but not limited to Cl⁻, Br⁻,Fl⁻, NO₃ ⁻, NO₂ ⁻, NO⁻, HCO₃ ⁻, CO₃ ²⁻, SO₄ ²⁻, and/or PO₄ ³⁻;biological molecules, such as proteins, oligopeptides, polypeptides,oligonucleotides, nucleic acids, nucleic acid constructs, plasmids,viral particles; an/or organic polymers and co-polymers.

[0066] PTTG carboxy-terminal-related polynucleotides or PTTG-C peptidescan be, but are not necessarily, directly bound to the cellularuptake-enhancing agent. For example, the polynucleotide can be containedin an expression vector or other nucleic acid construct, which vector orother construct is bound to the uptake-enhancing agent at some moiety orpart of he vector or construct not directly linked to the PTTGcarboxy-terminal-related polynucleotide; for purposes of the presentinvention, the PTTG carboxy-terminal-related polynucleotide is still“complexed” with the uptake-enhancing agent, although not being directlybound to the uptake-enhancing agent by a chemical bond. As long as thepolynucleotide and the uptake enhancing agent are both constituents ormembers of the same complex, an indirect chemical linkage suffices. Anexample with respect to PTTG-C peptides, is an intervening third peptidesequence linking a first PTTG-C peptide segment with a second celluptake-enhancing and/or importation-competent peptide segment. The firstand second peptide segments, indirectly linked, are “complexed” forpurposes of the invention.

[0067] Examples of uptake-enhancing agents usefully complexed with thepolynucleotide include cationic or polycationic lipid-DNA orliposome-DNA complexes (“lipoplexes”). Such lipoplexes can, optionally,also be coated with serum albumin or formulated as large-sizedcolloidally unstable complexes to further enhance transfectionefficiency; the presence of calcium di-cations (Ca²⁺) can also enhancelipid-based transfection efficiency. (E.g., Simoes, S. et al., Humanserum albumin enhances DNA transfection by lipoplexes and confersresistance to inhibition by serum, Biochim. Biophys. Acta 1463(2):459-69[2000]; Turek, J. et al., Formulations which increase the size oflipoplexes prevent serum-associated inhibition of transfection, J. GeneMed. 2(1):32-40 [2000]; Zudam, N. J. et al., Lamellarity of cationicliposomes and mode of preparation of lipoplexes affect transfectionefficiency, Biochim. Biophys. Acta 1419(2): 207-20 [1999]; Lam, A M. andCullis, P. R., Calcium enhances the transfection potency of plasmidDNA-cationic liposome complexes, Biochim. Biophys. Acta 1463(2):279-290[2000]).

[0068] Inventive compositions can include negatively charged ternarycomplexes of cationic liposomes, transferrin or fusigenic peptide(s) orpoly(ethylenimine). (E.g., Simoes, S. et al., Gene delivery bynegatively charged ternary complexes of DNA, cationic liposomes andtransferrin orfusigenic peptides, Gene Ther. 5(7):955-64 [1998]).Liposomal uptake-enhancing agents complexed with inventivepolynucleotide(s) can also be encapsulated in polyethylene glycol (PEG),FuGENE6, or the like. (E.g., Saravolac, E.G., et al., Encapsulation ofplasmid DNA in stabilized plasmid-lipid particles composed of differentcationic lipid concentration for optimal transfection activity, J. DrugTarget 7(6):423-37 [2000]; Yu, R. Z. et al., Pharmacokinetics and tissuedisposition in monkeys of an antisense oligonucleotide inhibitor ofHa-ras encapsulated in stealth liposomes, Pharm. Res. 16(8):1309-15[1999]; Tao, M. et al., Specific inhibition of human telomerase activityby transfection reagent, FuGENE6-antisense phophorothioateoligonucleotide complex in HeLa cells, FEBS Lett 454(3):312-6 [1999]).

[0069] In some embodiments, the uptake of antisense oligonucleotides isalso enhanced by complexation with biocompatible polymeric orco-polymeric nanoparticles, for example, comprising alginate,aminoalkylmethacrylate, methylmethacrylate, polymethylmethacrylate,methylaminoethyl-methacrylate, polyalkylcyanoacrylate (e.g.,polyhexylcyanoacrylate), or the like. (E.g., Aynie, I. et al.,Spongelike alginate nanoparticles as a new potential system for thedelivery of antisense oligonucleotides, Antisense Nucleic Acid Drug Dev.9(3):301-12 [1999]; Zimmer, A., Antisense oligonucleotide delivery withpolyhexylcyanoacrylate nanoparticles as carriers, Methods 18(3):286-95,322 [1999]; Berton, M. et al., Highly loaded nanoparticulate carrierusingan hydrophobic antisense oligonucleotide complex, Eur. J. Pharm.Sci. 9(2): 163-70 [1999]; Zobel, H. P. et al., Evaluation ofaminoalkylmethacrylate nanoparticles as colloidal drug carrier systems.Part II: characterization of antisense oligonucleotides loaded copolymernanoparticles, Eur. J. Pharm. Biopharm. 48(1):1-12 [1999]; Fattal, E. etal., Biodegradable polyalkylcyanoacrylate nanoparticlesfor the deliveryof oligonucleotides, J. Controlled Release 53(1-3):137-43 [1998]).

[0070] Other useflul uptake-enhancing agents for complexing withpolynucleotides include starburst polyamidoamine (PAMAM) dendrimers. (Eg., Yoo, H. et al., PAMAM dendrimers as delivery agents for antisenseoligonucleotides, Pharm. Res. 16(12): 1799-804 [1999]; Bielinska, A. U.et al., Application of membrane-based dendrimer/DNA complexes for solidphase transfection in vitro and in vivo, Biomaterials 21(9): 877-87[2000]; Bielinska, A. U. et al., DNA complexing with polyamidoaminedendrimers: implicationsfor transfection, Bioconjug. Chem. 10(5):843-50[1999]; Bielinska, A.U. et al., Regulation of in vitro gene expressionusing antisense oligonucleotides or antisense expression plasmidstransfected using starburst PAMAM dendrimers, Nucleic Acid Res. 24(11):2176-82 [1996]; Kukowska-Latallo, J. F. et al., Efficient transfer ofgenetic material into mammalian cells using Starburst polyamidoaminedendrimers, Proc. Natl. Acad. Sci. USA 93(10):4897-902 [1996]; Delong,R. et al., Characterization of complexes of oligonucleotides withpolyamidoamine starburst dendrimers and effects on intracellulardelivery, J. Pharm. Sci. 86(6):762-64 [1997]).

[0071] Other preferred uptake-enhancing agents include lipofectin,lipfectamine, DIMRIE C, Superfect, Effectin (Qiagen), unifectin,maxifectin, DOTMA, DOGS (Transfectam; dioctadecylamidoglycylspermine),DOPE (1,2-dioleoyl-sn-glycero-3-phosphoethanolamine), DOTAP(1,2-dioleoyl-3-trimethylammonium propane), DDAB (dimethyldioctadecylammonium bromide), DHDEAB(N,N-di-n-hexadecyl-N,N-dihydroxyethyl ammonium bromide), HDEAB(N-n-hexadecyl-N,N-dihydroxyethylammonium bromide), polybrene, orpoly(ethylenimine) (PEI), and/or peptides, such as polylysine,protamine, pK17, peptide K8, and peptide p2. (E.g., Ferkol, Jr. et. al.,U.S. Pat. Nos., 5,972,900 and 5,972,901; Vaysse, L. and Arveiler, B.,Transfection usingsynthetic peptides: comparison of three DNA-compactingpeptides and effect of centrifugation, Biochim. Biophys. Acta1474(2):244-50 [2000]; Ni, Y. H. et al., Protamine enhance theefficiency of liposome-mediated gene transfer in a cultured humanhepatoma cell line, J. Formos Med. Assoc. 98(8):562-66 [1999]; Banerjee,R. et al., Novel series of non-glycerol-based cationic transfectionlipids for use in liposomal gene delivery, J. Med. Chem. 42(21):4292-99[1999]; Godbey, W. T. et al., Improved packing of poly(ethylenimine/DNAcomplexes increases transfection efficiency, Gene Ther. 6(8):1380-88[1999]; Kichler, A et al., Influence of the DNA complexation medium onthe transfection efficiency of lipospermine/DNA particles, Gene Ther.5(6):855-60 [1998]; Birchaa, J. C. et al., Physico-chemicalcharacterisation and transfection efficiency of lipid-based genedelivery complexes, Int. J. Pharm. 183(2):195-207 [1999]). Thesenon-viral cellular uptake-enhancing agents have the advantage that theyfacilitate stable integration of xenogeneic DNA sequences into thevertebrate genome, without size restrictions commonly associated withvirus-derived transfecting or transducing agents.

[0072] Another example, a viral cellular uptake-enhancing agent, is theadenovirus enhanced transferrin-polylysine-mediated gene delivery systemhas been described and patented by Curiel et al. (Curiel D. T., et al.,Adenovirus enhancement of transferrin-polylysine-mediated gene delivery,PNAS USA 88: 8850-8854 (1991). The delivery of DNA depends uponendocytosis mediated by the transferrin receptor (Wagner et al.,Transferrin-polycation conjugates as carriers for DNA uptake into cells,PNAS (USA) 87 3410-3414 (1990). In addition this method relies on thecapacity of adenoviruses to disrupt cell vesicles, such as endosomes andrelease the contents entrapped therein. This system can enhance the genedelivery to mammalian cells by as much as 2,000 fold over other methods.

[0073] The amount of each component of the composition is chosen so thatthe gene modification, e.g., by transfection or transduction, of amammalian cell is optimized. Such optimization requires no more thanroutine experimentation. The ratio of polynucleotide to lipid is broad,preferably about 1:1, although other effective proportions can also beutilized depending on the type of lipid uptake-enhancing agent andpolynucleotide utilized (E.g., Banerjee, R. et al. [1999]; Jaaskelainen,I. et al., A lipid carrier with a membrane active component and a smallcomplex size are required for efficient cellular delivery of anti-sensephosphorothioate oligonucleotides, Eur. J. Pharm. Sci. 10(3):187-193[2000]; Sakurai, F. et al., Effect of DNA/liposome mixing ratio on thephysicochemical characteristics, cellular uptake and intracellulartrafficking of plasmid DNA/cationic liposome complexes and subsequentgene expression, J. Controlled Release 66(2-3):255-69 [2000]).

[0074] A suitable amount of the inventive polynucleotide to be deliveredto the cells, in accordance with the method, preferably ranges fromabout 0.1 nanograms to about 1 milligram per gram of tumor tissue, invivo, or about 0. I nanograms to about 1 microgram per 5000 cells, invitro. Suitable amounts for particular varieties of PTTG-C-relatedpolynucleotides and/or cell types and/or for various mammalian subjectsundergoing treatment, can be determined by routine experimentation. Forexample, malignant cell lines, such as MCF-7 or HeLa, typically are moreefficiently transfected by the inventive PTTG-C-related polynucleotidesthan non-malignant cell lines. Also, those skilled in the art are awarethat there is typically considerable variability among individual cancerpatients to any single treatment regimen, therefore, the practitionerwill tailor any embodiment of the inventive method to each individualpatient as appropriate.

[0075] In some preferred embodiments, the polynucleotide can bedelivered into the mammalian cell, either in vivo or in vitro usingsuitable expression vectors well-known in the art (e.g., retroviralvectors, adenovirus vectors, and the like). In addition, to inhibit thein vivo expression of PTTG, the introduction by expression vector of theantisense strand of a DNA encoding a PTTG-C peptide is contemplated.

[0076] Suitable expression vectors are well-known in the art, andinclude vectors capable of expressing DNA operatively linked to aregulatory sequence, such as a promoter region that is capable ofregulating expression of such DNA. Thus, an expression vector refers toa recombinant DNA or RNA construct, such as a plasmid, a phage,recombinant virus or other vector that, upon introduction into anappropriate host cell, results in expression of the inserted DNA.Appropriate expression vectors are well known to those of skill in theart and include those that are replicable in eukaryotic cells and/orprokaryotic cells and those that remain episomal or those whichintegrate into the host cell genome.

[0077] Exemplary, eukaryotic expression vectors, include the clonedbovine papilloma virus genome, the cloned genomes of the murineretroviruses, and eukaryotic cassettes, such as the pSV-2 gpt system(described by Mulligan and Berg, 1979, Nature Vol. 277:108-114) theOkayama-Berg cloning system (Mol. Cell Biol. Vol. 2:161-170, 1982),pGAL4, pCI (e.g., pCI-neo), and the expression cloning vector describedby Genetics Institute (Science Vol. 228:810-815, 1985), are availablewhich provide substantial assurance of at least some expression of theprotein of interest in the transformed mammalian cell.

[0078] Particularly preferred are vectors which contain regulatoryelements that can be linked to the inventive PTTG-encoding DNAs, such asa PTTG-C-encoding DNA segment, for transfection of mammalian cells.Examples are cytomegalovirus (CMV) promoter-based vectors such as pcDNAI(Invitrogen, San Diego, Calif.), MMTV promoter-based vectors such aspMAMNeo (Clontech, Palo Alto, Calif.) and pMSG (Pharmacia, Piscataway,N.J.), and SV40 promoter-based vectors such as pSVβ (Clontech, PaloAlto, Calif.).

[0079] In one embodiment of the present invention,adenovirus-transferrin/polylysine-DNA (TfAdpl-DNA) vector complexes(Wagner et al., 1992, PNAS, USA, 89:6099-6103; Curiel et al., 1992, Hum.Gene Therapy, 3:147-154; Gao et al., 1993, Hum. Gene Ther., 4:14-24) areemployed to transduce mammalian cells with heterologous PTTG-specificnucleic acid. Any of the plasmid expression vectors described herein maybe employed in a TfAdpl-DNA complex.

[0080] In addition, vectors may contain appropriate packaging signalsthat enable the vector to be packaged by a number of viral virions,e.g., retroviruses, herpes viruses, adenoviruses, resulting in theformation of a “viral vector.”

[0081] “Virus”, as used herein, means any virus, or transfectingfragment thereof, which can facilitate the delivery of thepolynucleotide into mammalian cells. Examples of viruses which aresuitable for use herein are adenoviruses, adeno-associated viruses,retroviruses such as human immune-deficiency virus, lentiviruses, mumpsvirus, and transfecting fragments of any of these viruses, and otherviral DNA segments that facilitate the uptake of the desired DNA segmentby, and release into, the cytoplasm of germ cells and mixtures thereof.A preferred viral vector is Moloney murine leukemia virus and theretrovirus vector derived from Moloney virus calledvesicular-stomatitis-virus-glycoprotein (VSV-G)-Moloney murine leukemiavirus. A most preferred viral vector is a pseudotyped (VSV-G) lentiviralvector derived from the HIV virus. (Naldini et al. [1996]). Also, themumps virus is particularly suited because of its affinity for immaturesperm cells including spermatogonia. All of the above viruses mayrequire modification to render them non-pathogenic or less antigenic.Other known viral vector systems, however, are also useful within theconfines of the invention.

[0082] Viral based systems provide the advantage of being able tointroduce relatively high levels of the heterologous nucleic acid into avariety of cells. Suitable viral vectors for introducing inventivePTTG-specific polynucleotides into mammalian cells (e.g., vasculartissue segments) are well known in the art. These viral vectors include,for example, Herpes simplex virus vectors (e.g., Geller et al., 1988,Science, 241:1667-1669), Vaccinia virus vectors (e.g., Piccini et al.,1987, Meth. in Enzymology, 153:545-563; Cytomegalovirus vectors(Mocarski et al., in Viral Vectors, Y. Gluzman and S. H. Hughes, Eds.,Cold Spring Harbor Laboratory, Cold Spring Harbor, N Y., 1988, pp.78-84), Moloney murine leukemia virus vectors (Danos et al., 1980, PNAS,USA, 85:6469), adenovirus vectors (e.g., Logan et al., 1984, PNAS, USA,81:3655-3659; Jones et al., 1979, Cell, 17:683-689; Berkner, 1988,Biotechniques, 6:616-626; Cotten et al., 1992, PNAS, USA, 89:6094-6098;Graham et al., 1991, Meth. Mol. Biol., 7:109-127), adeno-associatedvirus vectors, retrovirus vectors (see, e.g., U.S. Pat. Nos. 4,405,712and 4,650,764), and the like. Especially preferred viral vectors are theadenovirus and retroviral vectors.

[0083] As used herein, “retroviral vector” refers to the well-known genetransfer plasmids that have an expression cassette encoding anheterologous gene residing between two retroviral LTRs. Retroviralvectors typically contain appropriate packaging signals that enable theretroviral vector, or RNA transcribed using the retroviral vector as atemplate, to be packaged into a viral virion in an appropriate packagingcell line (see, e.g., U.S. Pat. No. 4,650,764). Retroviral vectorsinclude lentiviral vectors, such as HIV-derived vectors.

[0084] Suitable retroviral vectors for use herein are described, forexample, in U.S. Pat. No. 5,252,479, and in WIPO publications WO92/07573, WO 90/06997, WO 89/05345, WO 92/05266 and WO 92/14829,incorporated herein by reference, which provide a description of methodsfor efficiently introducing nucleic acids into human cells using suchretroviral vectors. Other retroviral vectors include, for example, themouse mammary tumor virus vectors (e.g., Shackleford et al., 1988, PNAS,USA, 85:9655-9659), and the like.

[0085] A most preferred embodiment employs a pseudotyped retroviralvector system, which was developed for gene therapy. (Naldini, L., etal., In vivo gene delivery and stable transduction of nondividing cellsby a lentiviral vector, Science 272: 263-267 [1996]), and which is usedto transduce mammalian cells. This gene delivery system employsretroviral particles generated by a three-plasmid expression system. Inthis system a packaging construct contains the human cytomegalovirus(hCMV) immediate early promoter, driving the expression of all viralproteins. The construct's design eliminates the cis-acting sequencescrucial for viral packaging, reverse transcription and integration ofthese transcripts. The second plasmid encodes a heterologous envelopeprotein (env), namely the G glycoprotein of the vesicular stomatitisvirus (VSV-G). The third plasmid, the transducing vector (pHR′),contains cis-acting sequences of human immunodeficiency virus (HIV)required for packaging, reverse transcription and integration, as wellas unique restriction sites for cloning heterologous complementary DNAs(cDNAs). For example, a genetic selection marker, such as greenfluorescent protein (GFP), enhanced green fluorescent protein (EGFP),blue fluorescent protein, yellow fluorescent protein, β-galactosidase,and/or a gene encoding another preselected product is cloned downstreamof the hCMV promoter in the HR vector, and is operatively linked so asto form a transcriptional unit. A VSV-G pseudotyped retroviral vectorsystem is capable of infecting a wide variety of cells including cellsfrom different species and of integrating into the genome. Someretroviruses, i.e., lentiviruses, such as HIV, have the ability toinfect non-dividing cells. Lentiviruses have a limited capacity forheterologous DNA sequences, the size limit for this vector being 7-7.5kilobases (Verma, I.M. and Somia, N., Gene Therapy—promises, problemsand prospects, Nature 389:239-242 [1997]). In vivo experiments withlentiviruses show that expression does not shut off like otherretroviral vectors and that in vivo expression in brain, muscle, liveror pancreatic-islet cells, is sustained at least for over six months—thelongest time tested so far (Verma and Somia [1997]; Anderson, W F.,Human Gene Therapy, Nature (Suppl). 392:25-30 [1998]).

[0086] “Gene delivery (or transfection) mixture”, in the context of thispatent, means a selected PTTG carboxy-terminal-related polynucleotide,whether in sense or anti-sense orientation, together with an appropriatevector mixed, for example, with an effective amount of uptake-enhancingagent as described above. (E.g., Clark et al., Polycations and cationiclipids enhance adenovirus transduction and transgene expression in tumorcells, Cancer Gene Ther 6(5): 437-46 [1999]). For example, theefficiency of adenoviral-, retroviral-, or lentiviral-mediatedtransduction is enhanced significantly by including a cationic lipid,such as polybrene during the infection.

[0087] In peptide-based embodiments of the inventive method ofinhibiting neoplastic cellular proliferation and/or transformation,involves delivering an inventive composition comprising a PTTGcarboxy-terminal peptide, which is interchangeably designated herein“PTTG-C” or “PTTG C-terminal peptide”.

[0088] The terms “protein”, “peptide”, and “polypeptide” are usedinterchangeably herein. As used herein, the phrase “PTTG” refers toprotein member of a mammalian family of PTTG proteins, formerly alsoknown as “pituitary-tumor-specific-gene” (PTSG) proteins, that are ableto transform mammalian cells in tissue culture (e.g., NIH 3T3 and thelike).

[0089] In vivo, PTTG proteins are further characterized by having theability to induce tumor formation, for example, in nude mice (e.g., whentransfected into NIH 3T3 and the like). PTTG proteins include naturallyoccurring allelic variants thereof encoded by mRNA generated byalternative splicing of a primary transcript, and further includefragments thereof which retain at least one native biological activity.

[0090] The term “biologically active” or “functional”, when used hereinas a modifier of inventive PTTG protein(s), peptide(s), or fragmentsthereof, refers to a polypeptide that exhibits at least one of thefunctional characteristics attributed to PTTG. For example, onebiological activity of PTTG is the ability to transform cells in vitro(e.g., NIH 3T3 and the like). Yet another biological activity of PTTG isthe ability to induce neoplastic cellular proliferation (e.g.,tumorigenesis) in nude mice (e.g., when transfected into NIH 3T3 cellsand the like).

[0091] On the other hand, the inventive PTTG-C peptide, as distinct fromthe full length native PTTG protein, has the biological activity ofinhibiting PTTG-mediated tumorigenesis in a dominant negative manner.“Dominant negative” is commonly used to describe a gene or protein whichhas a dominant effect similar to that described genetically, i.e onecopy of the gene gives a mutant phenotypic effect, and a negative effectin that it prevents or has a negative impact on a biological processsuch as a signal transduction pathway. Thus, PTTG carboxy-terminalpeptides have the ability to downregulate intracellular PTTG expressionand/or endogenous PTTG function. The inventive method is not limited toany particular biochemical, genetic, and/or physiological mechanism(s)by which a PTTG-C peptide exerts its biological activity on PTTGexpression and/or PTTG function, and any or all such mechanism(s) cancontribute to the biological activity of PTTG-C, in accordance with theinvention.

[0092] Another biological activity of PTTG or PTTG-C peptides is theability to act as an immunogen for the production of polyclonal andmonoclonal antibodies that bind specifically to PTTG and/or PTTG-C.Thus, an inventive nucleic acid encoding PTTG or PTTG-C will encode apolypeptide specifically recognized by an antibody that alsospecifically recognizes a PTTG protein as described herein. Suchactivity may be assayed by any method known to those of skill in theart. For example, a test-polypeptide encoded by a PTTG cDNA can be usedto produce antibodies, which are then assayed for their ability to bindto the protein. If the antibody binds to the test-polypeptide and theprotein with substantially the same affinity, then the polypeptidepossesses the requisite biological activity with respect toimmunogenicity.

[0093] In the method of inhibiting neoplastic cellular proliferationand/or transformation of a mammalian cell, whether in vitro or in vivo,useful PTTG-C peptides encompass also any fragment of a larger PTTG-Cmolecule, which fragment retains PTTG-C biological activity with respectto downregulating endogenous PTTG expression and/or endogenous PTTGfunction. Useful PTTG-C peptides are preferably, but not exclusively,about 15 to about 60 contiguous amino acid residues long and compriseone or more proline-rich regions, which are peptide segments having aPXXP motif, where the Xs between the proline (P) residues represent anyamino acid residue, including proline. The proline-rich region(s) of thePTTG-C peptide is a potential SH3-binding site.

[0094] Most preferably, the PTTG-C peptide is derived from a human PTTG,also designated hPTTG or PTTG1 protein. The native human PTTGI proteinis 202 amino acids long, having the following amino acid sequence (Table7 below; encoded by nucleotide positions 95 through 700 of human PTTG1sequence SEQ. ID.NO.:3 and degenerate sequences). TABLE 7 PTTG1 aminoacid sequence. 1 MATLTYVDKE NGEPGTRVVA KDGLKLGSGP SIKALDGRSQ VSTPRFGKTF(SEQ. ID. NO.:4) 51 DAPPALPKAT RKALGTVNRA TEKSVKTKGP LKQKQPSFSAKKMTEKTVKA 101 KSSVPASDDA YPETEKFFPF NPLDFESFDL PEEHQIAHLP LSGVPLMILD151 EERELEKLFQ LGPPSPVKMP SPPWESNLLQ SPSSILSTLD VELPPVCCDI 201 DI

[0095] The human PTTG1 peptide is also encoded by any degenerate codingsequence encoding the amino acid sequence of SEQ. ID. NO.:4.

[0096] A preferred PTTG-C has the amino acid sequence corresponding toamino acid residues 147 through 202 of SEQ. ID. NO.:4 (Table 8 below;encoded by nucleotide positions 533 through 700 of SEQ. ID. NO.:3 or1-168 of SEQ. ID. NO.:10 and degenerate sequences). TABLE 8 Human PTTG-Camino acid sequence. MTLDEERELE KLFQLGPPSP VKMPSPPWES NLLQSPSSILSTLDVELPPV CCDIDI. 56 (SEQ. ID. NO.9)

[0097] There are at least two proline-rich regions between amino acidresidues 163-173 of SEQ. ID. NO.:4, which correspond to amino acidresidues 17 through 27 of SEQ. ID. NO.:9, encoded by nucleotides 49through 81 of SEQ. ID. NO.:10 and degenerate sequences. Proline-richregions are found at amino acid residues 163-167 and 170-173 of SEQ. ID.NO.:4, corresponding to amino acid residues 17-20 and 24-27 of SEQ. ID.NO.:9. Other useful smaller peptide fragments of SEQ. ID. NO.:9 aretested by routine means for their effectiveness in inhibiting neoplasticcellular proliferation and/or transformation of a cell.

[0098] Another example of a PTTG protein is a rat PTTG having thefollowing amino acid sequence (Table 9 below; encoded by nucleotidepositions 293-889 of SEQ. ID. NO.:1 and degenerate sequences). TABLE 9Rat PTTG amino acid sequence. Met Ala Thr Leu Ile Phe Val Asp Lys AspAsn Glu Glu Pro Gly Ser 16 (SEQ. ID. NO.:2) Arg Leu Ala Ser Lys Asp GlyLeu Lys Leu Gly Ser Gly Val Lys Ala 32 Leu Asp Gly Lys Leu Gln Val SerThr Pro Arg Val Gly Lys Val Phe 48 Gly Ala Pro Gly Leu Pro Lys Ala SerAla Lys Ala Leu Gly Thr Val 64 Asn Ala Val Thr Glu Lys Pro Val Lys SerSer Lys Pro Leu Gln Ser 80 Lys Gln Pro Thr Leu Ser Val Lys Lys Ile ThrGlu Lys Ser Thr Lys 96 Thr Gln Gly Ser Ala Pro Ala Pro Asp Asp Ala TyrPro Glu Ile Glu 112 Lys Phe Phe Pro Phe Asp Pro Leu Asp Phe Glu Ser PheAsp Leu Pro 128 Glu Glu His Gln Ile Ser Leu Leu Pro Leu Asn Gly Val ProLeu Met 144 Ile Leu Asn Glu Glu Ala Gly Leu Glu Lys Leu Leu His Leu AspPro 160 Pro Ser Pro Leu Gln Lys Pro Phe Leu Pro Trp Glu Ser Asp Pro Leu176 Pro Ser Pro Pro Ser Ala Leu Ser Ala Leu Asp Val Glu Leu Pro Pro 192Val Cys Tyr Asp Ala Asp Ile. 199

[0099] A rat PTTG-C peptide includes amino acid residues 144 through 199of SEQ. ID. NO.:2, i.e., SEQ. ID. NO.:16 (Table 10 below; encoded bynucleotide positions 722 through 889 of SEQ. ID. NO.:1 or 1-168 of SEQ.ID. NO.:18 and degenerate sequences). TABLE 10 Rat PTTG-C aminosequence. Met Ile Leu Asn Glu Glu Ala Gly Leu Glu Lys Leu Leu His LeuAsp 16 SEQ. ID. NO.:16 Pro Pro Ser Pro Leu Gln Lys Pro Phe Leu Pro TrpGlu Ser Asp Pro 32 Leu Pro Ser Pro Pro Ser Ala Leu Ser Ala Leu Asp ValGlu Leu Pro 48 Pro Val Cys Tyr Asp Ala Asp Ile 56

[0100] SEQ. ID. NO.:16

[0101] The amino acid sequence of SEQ. ID. NO.:16 includes proline-richregions at amino acid residues 17-20, 24-27, and 34-37 (corresponding toamino acid residues 160-163, 167-170, and 177-180 of SEQ. ID. NO.:2).

[0102] Another example of a PTTG protein is a murine PTTG having thefollowing amino acid sequence (Table 11 below; encoded by nucleotidepositions 304 through 891 of SEQ. ID. NO.:15 and degenerate sequences).TABLE 11 Murine PTTG amino acid sequence. 1 MATLIFVDKD NEEPGRRLASKDGLKLGTGV KALDGKLQVS TPRVGKVFNA SEQ. ID. NO.: 14 51 PAVPKASRKALGTVNRVAEK PMKTGKPLQP KQPTLTGKKI TEKSTKTQSS 101 VPAPDDAYPE IEKFFPFNPLDFDLPEEHQI SLLPLNGVPL ITLNEERGLE 151 KLLHLGPPSP LKTPFLSWES DPLYSPPSALSTLDVELPPV CYDADI

[0103] A murine PTTG-C peptide includes amino acid residues 141 through196 of SEQ. ID. NO.:14, i.e., SEQ. ID. NO.:17 (Table 12 below; encodedby nucleotide positions 724 through 891 of SEQ. ID. NO.:15 or 1-168 ofSEQ. ID. NO.:19 and degenerate sequences).

[0104] Table 12. Murine PTTG-C Amino Acid Sequence.

[0105] ITLNEERGLE KLLHLGPPSP LKTPFLSWES DPLYSPPSAL STLDVELPPV CYDADI 56(SEQ. ID. NO.:17).

[0106] The amino acid sequence of SEQ. ID. NO.:17 includes aproline-rich region at amino acid residues 17-20 (corresponding to aminoacid residues 157-160 of SEQ. ID. NO.:14).

[0107] Preferred PTTG-C Peptides Include:

[0108] (A) peptides having an amino acid sequence of (SEQ. ID. NO.:9),(SEQ. ID. NO.:16), or (SEQ. ID. NO.:17); or

[0109] (B) mammalian PTTG-C peptides having at least about 60% sequencehomology with any of the sequences in (A); or

[0110] (C) peptide fragments of any of the sequences in (A) or (B) thatcomprise at least 15 contiguous amino acid residues and that function todownregulate endogenous PTTG expression and/or PTTG function. Mostpreferably, the fragment of (C) includes one or more proline-richregions.

[0111] Those of skill in the art will recognize that in other usefulPTTG-C peptides numerous residues of any of the above-described PTTG orPTTG-C amino acid sequences can be substituted with other, chemically,sterically and/or electronically similar residues without substantiallyaltering PTTG or PTTG-C biological activity. In addition, largerpolypeptide sequences containing substantially the same coding sequencesas in SEQ ID NO:2, SEQ. ID. NO.:4, SEQ. ID. NO.:9, SEQ. ID. NO.:14, SEQ.ID. NO.:16, or SEQ. ID. NO.:17 (e.g., splice variants) are contemplated.

[0112] As employed herein, the term “substantially the same amino acidsequence” refers to amino acid sequences having at least about 60%sequence homology or identity with respect to any of the amino acidsequences described herein (“reference sequences”), and retainingcomparable functional and biological activity characteristic of theprotein defined by the reference sequences described, particularly withrespect to neoplastic cellular proliferation and/or transformation orits inhibition. More preferably, proteins having “substantially the sameamino acid sequence” will have at least about 80%, still more preferablyabout 90% amino acid identity with respect to a reference amino acidsequence; with greater than about 95% amino acid sequence identity beingespecially preferred. It is recognized, however, that polypeptidecontaining less than the described levels of sequence identity arisingas splice variants or that are modified by conservative amino acidsubstitutions are also encompassed within the scope of the presentinvention. The degree of sequence homology is determined by conductingan amino acid sequence similarity search of a protein data base, such asthe database of the National Center for Biotechnology Information (NCBI;www.ncbi.nlm.nih.gov/BLAST/), using a computerized algorithm, such asPowerBLAST, QBLAST, PSI-BLAST, PHI-BLAST, gapped or ungapped BLAST, orthe “Align” program through the Baylor College of Medicine server(www.hgsc bcm.tmc.edu/seqdata). (E.g., Altchul, S. F., et al., GappedBLAST and PSI-BLAST: a new generation of protein database searchprograms, Nucleic Acids Res. 25(17):3389-402 [1997]; Zhang, J., &Madden, T L., PowerBLAST: a new network BLAST application forinteractive or automated sequence analysis and annotation, Genome Res.7(6):649-56 [1997]; Madden, T. L., et al., Applications of network BLASTserver, Methods Enzymol. 266:131-41 [1996]; Altschul, S. F., et al.,Basic local alignment search tool, J. Mol. Biol. 215(3):403-10 [1990]).

[0113] Also encompassed by the terms PTTG protein or PTTG-C peptide,respectively, are biologically functional or active peptide analogsthereof The term peptide “analog” includes any polypeptide having anamino acid residue sequence substantially identical to a sequencespecifically shown herein in which one or more residues have beenconservatively substituted with a functionally similar residue and whichdisplays the ability to mimic the biological activity of PTTG or PTTG-C,respectively, particularly with respect to neoplastic cellularproliferation and/or transformation or its inhibition as describedherein above. Examples of conservative substitutions include thesubstitution of one non-polar (hydrophobic) residue such as isoleucine,valine, leucine or methionine for another, the substitution of one polar(hydrophilic) residue for another such as between arginine and lysine,between glutamine and asparagine, between glycine and serine, thesubstitution of one basic residue such as lysine, arginine or histidinefor another, or the substitution of one acidic residue, such as asparticacid or glutamic acid for another.

[0114] The phrase “conservative substitution” also includes the use of achemically derivatized residue in place of a non-derivatized residue,provided that such polypeptide displays the requisite biologicalactivity.

[0115] “Chemical derivative” refers to a subject polypeptide having oneor more residues chemically derivatized by reaction of a functional sidegroup. Such derivatized molecules include, for example, those moleculesin which free amino groups have been derivatized to form aminehydrochlorides, p-toluene sulfonyl groups, carbobenzoxy groups,t-butyloxycarbonyl groups, chloroacetyl groups or formyl groups. Freecarboxyl groups may be derivatized to form salts, methyl and ethylesters or other types of esters or hydrazides. Free hydroxyl groups maybe derivatized to form O-acyl or O-alkyl derivatives. The imidazolenitrogen of histidine may be derivatized to form N-im-benzylhistidine.Also included as chemical derivatives are those peptides which containone or more naturally occurring amino acid derivatives of the twentystandard amino acids. For example, 4-hydroxyproline may be substitutedfor proline; 5-hydroxylysine may be substituted for lysine;3-methylhistidine may be substituted for histidine; homoserine may besubstituted for serine; and ornithine may be substituted for lysine. Theinventive polypeptide of the present invention also include anypolypeptide having one or more additions and/or deletions of residues,relative to the sequence of a polypeptide whose sequence is shownherein, so long as the requisite PTTG or PTTG-C biological activity ismaintained.

[0116] In accordance with peptide-based embodiments of the inventivemethod of inhibiting neoplastic cellular proliferation and/ortransformation, the composition comprising the PTTG-C peptide isdelivered to the cell. A suitable amount of the inventive PTTG-C peptideto be delivered to the cells, in accordance with the method, preferablyranges from about 0.1 nanograms to about 1 milligram per gram of tumortissue, in vivo, or about 0.1 nanograms to about 1 microgram per 5000cells, in vitro. Suitable amounts for particular varieties of PTTG-Cpeptide and/or cell types and/or for various individual mammaliansubjects undergoing treatment, can be determined by routineexperimentation.

[0117] Methods of delivering and importing peptides into target cellsare known. For example, the composition preferably, but not necessarily,comprises in addition to the PTTG-C peptide, a complex in which thePTTG-C peptide is complexed with a cellular uptake-enhancing agent. Forexample, the PTTG-C peptide can be covalently linked in a complex to acellular uptake-enhancing and/or importation-competent peptide segmentfor delivery of PTTG-C into the mammalian cell; in addition, a nuclearlocalization peptide can be included in the complex to direct the PTTG-Cto the nucleus. (E.g., Lin et al., Method for importing biologicallyactive molecules into cells, U.S. Pat. No. 6,043,339). An“importation-competent peptide,” as used herein, is a sequence of aminoacids generally of a length of about 10 to about 50 or more amino acidresidues, many (typically about 55-60%) residues of which arehydrophobic such that they have a hydrophobic, lipid-soluble portion.The hydrophobic portion is a common, major motif of a signal peptide,and it is often recognizable as a central part of the signal peptide ofa protein secreted from cells. A signal peptide is a peptide capable ofpenetrating through the cell membrane to allow the export of cellularproteins. Signal peptides useful in the present method are also“importation-competent,” i.e., capable of penetrating through the cellmembrane from outside the cell to the interior of the cell.

[0118] In a preferred embodiment, a PTTG-C peptide forms a first PTTG-Cpeptide segment of a chimeric or fusion protein. The chimeric or fusionprotein comprises at least the first PTTG-C peptide segment and a secondcellular uptake-enhancing and/or importation-competent peptide segment.The second segment of the chimeric or fusion protein is a cellularuptake-enhancing and/or importation-competent peptide segment, such as asignal peptide, that allows the hybrid molecule to enter neoplasticcells that overexpress PTTG, whether in vitro or in vivo. The secondpeptide segment, such as the human immunodeficiency virus (HIV) TATprotein (Schwarze, S. R., et al., In vivo protein transduction: deliveryof a biologically active protein into the mouse, Science 285:1569-72[1999]), infiltrates the cells, and once within the cells, the PTTG-Cpeptide segment of the fusion protein becomes active within the cells toinhibit endogenous PTTG expression and/or PTTG function. Another exampleof a useful uptake-enhancing peptide segment is the signal peptide fromKaposi fibroblast growth factor (K-FGF). But any cellularuptake-enhancing and/or importation-competent peptide segment, capableof translocating across the cell membrane into the interior of theselected target mammalian cell, can be used according to this invention.The chimeric or fusion protein can also include additional segments,such as a linker segment, that can be an intervening segment between thefirst and second segments. The additional segment can alternatively be aterminal segment, as appropriate.

[0119] In embodiments of the method involving the use of PTTG-C chimericor fusion proteins, the cellular uptake-enhancing and/orimportation-competent peptide segment can be the uptake-enhancing agent.Alternatively, or in addition, the cellular uptake-enhancing agent canbe a lipid or liposome uptake-enhancing agent as described herein above,such as lipofectin, lipofectamine, DOTAP, and others. Cationic (orpolycationic) lipids or liposomes can also be complexed with a signalpeptide and a negatively-charged biologically active molecule by mixingthese components and allowing them to charge-associate. Anionicliposomes generally are utilized to encapsulate within the liposome thesubstances to be delivered to the cell. Procedures for forming cationicliposome-encapsulating substances are standard in the art and canreadily be utilized herein by one of ordinary skill in the art toencapsulate the complex of this invention. For example, liposomeuptake-enhancing agents complexed with inventive PTTG-C peptidefragments can be encapsulated in polyethylene glycol (PEG), FuGENE6, orthe like.

[0120] With respect to delivery of the composition to mammalian cells invivo, the composition is administered to a mammalian subject in need oftreatment, including a human subject, by any conventional deliveryroute. Preferably, the PTTG-C peptide, whether or not complexed withcellular uptake-enhancing and/or importation-competent peptides (e.g.,signal or localization peptides), is injected intravenously,intra-arterially, intraperitoneally, or by means of injection directlyinto a tumor or into a cell by microinjection. Conventional stereotacticmethods can be useful for direct injection into tumors or cells. Inother preferred embodiments, controlled release formulations ofbiodegradable polymeric microspheres or nanospheres (e.g.,polylactide-co-glycolide; PLGA) encapsulating the PTTG-C peptide, orPTTG-C chimeric or fusion protein are administered to the mammaliansubject orally. (E.g., Zhu, G. et al., Stabilization of proteinsencapsulated in injectable poly(lactide-co-glycolide), NatureBiotechnology 18:52-57 [2000]). Administration by nasal, rectal, orvaginal delivery routes can also be useful. Administration by catheteror stent can also be useful for delivering the PTTG-C peptide.

[0121] In some embodiments, isolated and crystallized PTTG-C peptide canbe cross-linked with a multifunctional crosslinking agent that inhibitsproteolysis of the PTTG-C peptide in vivo. (Navia, M. A., Method ofprotein therapy by orally administering crosslinked protein crystals,U.S. Pat. No. 6,011,001).

[0122] In accordance with the inventive method of inhibiting neoplasticcellular proliferation and/or transformation that is mediated by PTTG,the mammalian cell is a cell that overexpresses PTTG, the gene thatencodes a PTTG protein. Although detecting PTTG overexpression by thecell is not essential or necessary to the practice of the inventivemethod, the level of PTTG expression, including overexpression, isdetectable by one skilled in the art. Detection of PTTG expression isaccomplished by immunochemical assay for PTTG protein, for example,using the inventive anti-PTTG-C antibodies, described herein, or otheranti-PTTG-specific antibodies. Alternatively, amplification ofPTTG-specific mRNAs present in biological samples (e.g., tissue biopsy)can be used to detect PTTG expression. This is done by known molecularbiological techniques of amplification and analysis of the amplificationproducts for the presence or absence of PTTG-specific amplificationproducts. If PTTG gene-specific amplification products are present, thefindings are indicative of expression of the PTTG gene and diagnostic ofthe presence of neoplastic cellular proliferation in the subject asdefined herein.

[0123] However, for interpretation of negatives (no PTTG-specificamplification products) analysis is preferably carried out following acontrol amplification of nucleic acids specific for a housekeeping gene,for example, a gene encoding β-actin, phosphofructokinase (PFK),glyceraldehyde 3-phosphate dehydrogenase, or phosphoglycerate kinase.Only if expression of the housekeeping gene is detected in the sample,is the absence of PTTG gene expression reliably accepted. Withincreasing sensitivity of amplification and analysis methods employed,it becomes increasingly preferable to determine the level of PTTG geneexpression relative to expression of a housekeeping gene, in order tobetter distinguish neoplastic, hyperplastic, cytologically dysplasticand/or premalignant cellular growth or proliferation from the detectablebackground of normal cellular division. The ratio of PTTG expression tohousekeeping gene expression is determined, for example, by real-timePCR methods or densitometric measurement and analysis of electrophoreticbands after amplification. When the ratio of PTTG expression tohousekeeping gene expression exceeds a normal cell standard range and/orapproximates an abnormal (e.g., neoplastic) cell standard range, thisindicates overexpression of PTTG gene product, characteristic ofneoplastic, hyperplastic, cytologically dysplastic and/or premalignantcellular growth or proliferation.

[0124] PTTG-specific mRNAs in a biological sample are amplified by asuitable amplification method. For example, a reversetranscriptase-mediated polymerase chain reaction (RT-PCR) is employed toamplify PTTG-specific nucleic acids. Briefly, two enzymes are used inthe amplification process, a reverse transcriptase to transcribePTTG-specific cDNA from a PTTG-specific mRNA template in the sample, athermal resistant DNA polymerase (e.g., Taq polymerase), andPTTG-specific primers to amplify the cDNA to produce PTTG gene-specificamplification products. The use of limited cycle PCR yieldssemi-quantitative results. (E.g., Gelfand et al., Reverse transcriptionwith thermostable DNA polymerase-high tempreature reverse transcription,U.S. Pat. Nos. 5,310,652; 5,322,770; Gelfand et al., Unconventionalnucleotide substitution in temperature selective RT-PCR, U.S. Pat. No.5,618,703).

[0125] Alternatively, single enzyme RT-PCR is employed to amplify PTTGgene-specific nucleic acids. Single enzymes now exist to perform bothreverse transcription and polymerase functions, in a single reaction.For example, the Perkin Elmer recombinant Thermus thermophilus (rTth)enzyme(Roche Molecular), or other similar enzymes, are commerciallyavailable.

[0126] Real-time RT-PCR can be employed to amplify PTTG-specific nucleicacids. Briefly, this is a quantitative gene analysis based on the ratioof PTTG gene expression and the expression of a housekeeping gene, i.e.,a gene that is expressed at about the same level in normal and abnormal(e.g., malignant) cells, for example, a gene encoding β-actin,phosphofructokinase, glyceraldehyde 3-phosphate dehydrogenase, orphosphoglyceratekinase. The the ratio of the PTTG and housekeepinggenes' expressions is routinely established as a standard for normal andabnormal cells, which standard expression ratio(s) is (are) used forcomparison in determining that expression of the PTTG gene relative toexpression of the “housekeeping” gene in a given sample is either“normal” or “increased”, the latter indicative of “overexpression” anddiagnostic for the presence of neoplastic, hyperplastic, cytologicallydysplastic and/or premalignant cellular growth or proliferation. In thisembodiment, the ratio is the key to diagnosis and constitutesquantitative gene expression analysis. This embodiment utilizesso-called real-time quantitative PCR, carried out with commerciallyavailable instruments, such as the Perkin Elmer ABI Prism 7700, theso-called Light Cycler (Roche Molecular), and/or other similarinstruments. Optionally, single enzyme RT-PCR technology, for example,employing rTth enzyme, can be used in a real-time PCR system.Preferably, amplification and analysis are carried out in an automatedfashion, with automated extraction of mRNA from a urine sediment sample,followed by real-time PCR, and fluorescence detection of amplificationproducts using probes, such as TaqMan or Molecular Beacon probes.Typically, the instrumentation includes software that providesquantitative analytical results during or directly following PCR withoutfurther amplification or analytical steps.

[0127] Alternatively, transcription-mediated amplification (TMA) isemployed to amplify PTTG gene-specific nucleic acids. (E.g., K Kamisangoet al., Quantitative detection of hepatitis B virus bytranscription-mediated amplification and hybridization protection assay,J. Clin. Microbiol. 37(2):310-14 [1999]; M. Hirose et al., New method tomeasure telomerase activity by transcription-mediated amplification andhybridization protection assay, Clin. Chem. 44(12)2446-52 [1998]).Rather than employing RT-PCR for the amplification of a cDNA, TMA uses aprobe that recognizes a PTTG-specific (target sequence) RNA; insubsequent steps, from a promoter sequence built into the probe, an RNApolymerase repetitively transcribes a cDNA intermediate, in effectamplifying the original RNA transcripts and any new copies created, fora level of sensitivity approaching that of RT-PCR. The reaction takesplace isothermally (one temperature), rather than cycling throughdifferent temperatures as in PCR.

[0128] Other useful amplification methods include a reversetranscriptase-mediated ligase chain reaction (RT-LCR), which has utilitysimilar to RT-PCR. RT-LCR relies on reverse transcriptase to generatecDNA from mRNA, then DNA ligase to join adjacent syntheticoligonucleotides after they have bound the target cDNA.

[0129] Amplification of a PTTG gene-specific nucleic acid segment of thesubject can be achieved using PTTG gene-specific oligonucleotide primersand primer sets as provided herein.

[0130] Optionally, high throughput analysis may be achieved by PCRmultiplexing techniques well known in the art, employing multiple primersets, for example primers directed not only to PTTG gene-specificnucleic acids, but to amplifying expression products of housekeepinggenes (controls) or of other potential diagnostic markers (e.g.,oncogenes), as well, such as MAG or telomerase, to yield additionaldiagnostic information. (E.g., Z. Lin et al., Multiplex genotypedetermination at a large number of gene loci, Proc. Natl. Acad. Sci. USA93(6):2582-87 [1996]; Demetriou et al., Method and probe for detectionof gene associated with liver neoplastic disease, U.S. Pat. No.5,866,329).

[0131] Hybridization analysis is a preferred method of analyzing theamplification products, employing one or more PTTG-specific probe(s)that, under suitable conditions of stringency, hybridize(s) with singlestranded PTTG-specific nucleic acid amplification products comprisingcomplementary nucleotide sequences. Hybridization refers to the bindingof complementary strands of nucleic acid (i.e., sense: antisense strandsor probe:target-DNA) to each other through hydrogen bonds, similar tothe bonds that naturally occur in chromosomal DNA. The amplificationproducts are typically deposited on a substrate, such as a cellulose ornitrocellulose membrane, and then hybridized with labeled PTTG-specificprobe(s), optionally after an electrophoresis. Conventional dot blot,Southern, Northern, or fluorescence in situ (FISH) hybridizationprotocols, in liquid hybridization, hybridization protection assays, orother semi-quantitative or quantitative hybridization analysis methodsare usefully employed along with the PTTG gene-specific probes of thepresent invention. Preferred probe-based hybridization conditionscomprise a temperature of about 37° C., a formamide concentration ofabout 20%, and a salt concentration of about 5× standard saline citrate(SSC; 20×SSC contains 3 M sodium chloride, 0 3 M sodium citrate, pH7.0). Such conditions will allow the identification of sequences whichhave a substantial degree of similarity with the probe sequence, withoutrequiring perfect homology. The phrase “substantial similarity” refersto sequences which share at least 50% homology. Stringency levels usedto hybridize a given probe with target-DNA can be readily varied bythose of skill in the art. Preferably, hybridization conditions will beselected which allow the identification of sequences having at leastabout 60% homology with the probe, while discriminating againstsequences which have a lower degree of homology with the probe.

[0132] As used herein, a “probe” is single-stranded DNA or RNA, or anucleic acid analog. The inventive probe is preferably 7 to 500nucleotides long, more preferably 14 to 150 nucleotides long, and mostpreferably at least 50 nucleotides long. The probe comprises, for atleast part of its length, a PTTG-specific nucleotide sequence at least 7to 15 contiguous nucleotides long, such that the probe hybridizes to aPTTG-specific single stranded nucleic acid under suitably stringenthybridization conditions Examples of PTTG-specific nucleotide sequencesare set forth in any of SEQ. ID. NOS.:1, 3, 10, 15, 18, or 19,preferably, but not necessarily, including 5′ and/or 3′ coding regionsthereof. In addition, the entire cDNA encoding region of an inventivePTTG-specific nucleotide sequence, or the entire sequence correspondingto SEQ. ID. NOS.:1, 3, 10, 15, 18, 19, or nucleotide sequencescomplementary to any of these, can be used as a probe. For example,probes comprising inventive oligonucleotide primer sequences, such as,but not limited to, SEQ. ID. NO.:8, can be labeled for use as probes fordetecting or analyzing PTTG-specific nucleic acid amplificationproducts. Any of the inventive isolated PTTG-C-related polynucleotidescan be used as probes or primers.

[0133] Alternatively, electrophoresis for analyzing amplificationproducts is done rapidly and with high sensitivity by using any ofvarious methods of conventional slab or capillary electrophoresis, withwhich the practitioner can optionally choose to employ any facilitatingmeans of nucleic acid fragment detection, including, but not limited to,radionuclides, UV-absorbance or laser-induced fluorescence. (K. Keparniket al., Fast detection of a (CA) 18 microsatellite repeat in the IgEreceptor gene by capillary electrophoresis with laser-inducedfluorescence detection, Electrophoresis 19(2);249-55 [1998]; H. Inoue etal., Enhanced separation of DNA sequencing products by capillaryelectrophoresis using a stepwise gradient of electric field strength, J.Chromatogr. A. 802(1): 179-84 [1998]; N. J. Dovichi, DNA sequencing bycapillary electrophoresis, Electrophoresis 18(12-13):2393-99 [1997]; H.Arakawa et al., Analysis of single-strand conformation polymorphisms bycapillary electrophoresis with laser induced fluorescence detection, J.Pharm. Biomed. Anal. 15(9-10):1537-44 [1997]; Y. Baba, Analysis ofdisease-causing genes and DNA-based drugs by capillary electrophoresis.Towards DNA diagnosis and gene therapy for human diseases, J. ChromatgrB. Biomed. Appl. 687(2):271-302 [1996]; K. C. Chan et al., High-speedelectrophoretic separation of DNA fragments using a short capillary, J.Chromatogr B. Biomed. Sci. Appl. 695(1):13-15 [1997]). Probes can belabeled by methods well-known in the art.

[0134] As used herein, the terms “label”, “tracer”, and “indicatingmeans” in their various grammatical forms refer to single atoms andmolecules that are either directly or indirectly involved in theproduction of a detectable signal. Any label or indicating means can belinked to PTTG-specific probes, primers, or amplification products, orPTTG proteins, peptides, peptide fragments, or anti-PTTG antibodymolecules. The label can be used alone or in conjunction with additionalreagents. Such labels are themselves well-known in the art. The labelcan be a fluorescent labeling agent that chemically binds to antibodiesor antigens without denaturation to form a fluorochrome (dye) that is auseful immunofluorescent tracer. A description of immunofluorescentanalytic techniques is found in DeLuca, “Immunofluorescence Analysis”,in Antibody As a Tool, Marchalonis et al., eds., John Wiley & Sons,Ltd., pp. 189-231 (1982), which is incorporated herein by reference Anyof diverse fluorescent dyes can optionally be used as a label, includingbut not limited to, SYBR Green I, Y1O-PRO-1, thiazole orange, Hex (i.e.,6-carboxy-2′,4′,7′,4,7-hexachlorofluoroscein), pico green, edans,fluorescein, FAM (i.e., 6-carboxyfluorescein), or TET (i.e., 4,7,2′,7′-tetrachloro-6-carboxyfluoroscein). (E.g., J. Skeidsvoll and P. M.Ueland, Analysis of double-stranded DNA by capillary electrophoresiswith laser-induced fluorescence detection using the monomeric dye SYBRgreen I, Anal. Biochem. 231(20): 359-65 [1995]; H. Iwahana et al.,Multiple fluorescence-based PCR-SSCP analysis using internal fluorescentlabeling of PCR products, Biotechniques 21(30:510-14, 516-19 [1996]).

[0135] The label can also be an enzyme, such as horseradish peroxidase(HRP), glucose oxidase, P-galactosidase, and the like. Alternatively,radionuclides are employed as labels. The linking of a label to asubstrate, i.e., labeling of nucleic acid probes, antibodies,polypeptide, and proteins, is well known in the art. For instance, aninvention antibody can be labeled by metabolic incorporation ofradiolabeled amino acids provided in the culture medium. See, forexample, Galfre et al., Meth. Enzymol., 73:3-46 (1981). Conventionalmeans of protein conjugation or coupling by activated functional groupsare particularly applicable. See, for example, Aurameas et al., Scand.J. Immunol., Vol. 8, Suppl. 7:7-23 (1978), Rodwell et al., Biotech.,3:889-894 (1984), and U.S. Pat. No. 4,493,795.

[0136] In accordance with yet another embodiment of the presentinvention, there are provided anti-PTTG antibodies having specificreactivity with PTTG polypeptides of the present invention. Antibodyfragments, for example Fab, Fab′, F(ab′)₂, or F(v) fragments, thatselectively or specifically bind a PTTG protein, PTTG-C peptide, orimmunogenic fragment of PTTG-C, are also encompassed within thedefinition of “antibody”.

[0137] Inventive antibodies can be produced by methods known in the artusing PTTG polypeptide, proteins or portions thereof, such as PTTG-Cpeptide or immunogenic fragments of PTTG-C, as antigens. For example,polyclonal and monoclonal antibodies can be produced by methods wellknown in the art, as described, for example, in Harlow and Lane,Antibodies: A Laboratory Manual (Cold Spring Harbor Laboratory [1988]),which is incorporated herein by reference. Isolated or purified PTTGproteins, PTTG-C peptides, and immunogenic PTTG-C fragments can be usedas immunogens in generating such specific antibodies.

[0138] PTTG proteins, PTTG-C peptides, or polypeptide analogs thereof,are purified or isolated by a variety of known biochemical means,including, for example, by the recombinant expression systems describedherein, precipitation, gel filtration, ion-exchange, reverse-phase andaffinity chromatography, and the like. Other well-known methods aredescribed in Deutscher et al., Guide to Protein Purification: Methods inEnzymology Vol. 182, (Academic Press, [1990]), which is incorporatedherein by reference. Isolated PTTG proteins or PTTG-C peptides are freeof cellular components and/or contaminants normally associated with anative in vivo environment.

[0139] Isolated PTTG proteins or PTTG-C peptides can also be chemicallysynthesized For example, synthetic polypeptide can be produced usingApplied Biosystems, Inc. Model 430A or 431A automatic peptidesynthesizer (Foster City, Calif.) employing the chemistry provided bythe manufacturer. Alternatively, PTTG can be isolated or purified fromnative sources, and PTTG-C peptides can be isolated from PTTG (or fromchimeric proteins) by the use of suitable proteases.

[0140] Alternatively, PTTG or PTTG-C polypeptides can be recombinantlyderived, for example, produced by mammalian cells genetically modifiedto express PTTG-C-encoding polynucleotides in accordance with theinventive technology as described herein. Recombinant methods are wellknown, as described, for example, in Sambrook et al., supra., 1989). Anexample of the means for preparing the inventive PTTG or PTTG-Cpolypeptide(s) is to express nucleic acids encoding the PTTG protein orPTTG-C peptide in a suitable host cell, such as a bacterial cell, ayeast cell, an amphibian cell (i.e., oocyte), or a mammalian cell, suchas the inventive mammalian host cell described herein below, usingmethods well known in the art, and recovering the expressed polypeptide,again using well-known methods.

[0141] The immunogenicity of various PTTG-C fragments of interest isdetermined by routine screening. Alternatively, synthetic PTTG or PTTG-Cpolypeptides or fragments thereof can be prepared (using commerciallyavailable synthesizers) and used as immunogens. Amino acid sequences canbe analyzed by methods well known in the art to determine whether theyencode hydrophobic or hydrophilic domains of the correspondingpolypeptide. Altered antibodies such as chimeric, humanized, CDR-graftedor bifunctional antibodies can also be produced by methods well known inthe art. Such antibodies can also be produced by hybridoma, chemicalsynthesis or recombinant methods described, for example, in Sambrook etal., supra., and Harlow and Lane, supra. Both anti-peptide andanti-fusion protein antibodies can be used. (see, for example, Bahouthet al., Trends Pharmacol Sci. 12:338 [1991]; Ausubel et al., CurrentProtocols in Molecular Biology (John Wiley and Sons, NY [1989] which areincorporated herein by reference).

[0142] Antibody so produced can be used, inter a/ia, in diagnostic orassay methods and systems to detect the level of PTTG protein, PTTG-Cpeptide, or immunogenic fragments thereof, present in a mammalian,preferably human, biological sample, such as tissue or vascular fluid.This is useful, for example, in determining the level of PTTGexpression. Such antibodies can also be used for the immunoaffinity oraffinity chromatography purification of the inventive PTTG proteins orPTTG-C peptides. In addition, methods are contemplated herein fordetecting the presence of PTTG protein or PTTG-C peptide, either on thesurface of a cell or within a cell (such as within the nucleus), whichmethods comprise contacting the cell with an antibody that specificallybinds to PTTG protein or PTTG-C peptide, under conditions permittingspecific binding of the antibody to PTTG protein or PTTG-C peptide,detecting the presence of the antibody bound to PTTG or PTTG-C, andthereby detecting the presence of PTTG or PTTG-C polypeptide on thesurface of, or within, the cell. With respect to the detection of suchpolypeptide, the antibodies can be used for in vitro diagnostic or assaymethods, or in vivo imaging methods.

[0143] Immunological procedures useful for in vitro detection of targetPTTG or PTTG-C polypeptides in a sample include immunoassays that employa detectable antibody. Such immunoassays include, for example, ELISA,immunofluorescence assay (IFA), Pandex microfluorimetric assay,agglutination assays, flow cytometry, serum diagnostic assays andimmunohistochemical staining procedures which are well known in the art.An antibody can be made detectable by various means well known in theart. For example, a detectable marker can be directly or indirectlyattached to the antibody. Useful markers include, for example,radionuclides, enzymes, fluorogens, chromogens and chemiluminescentlabels.

[0144] Inventive anti-PTTG or anti-PTTG-C antibodies are alsocontemplated for use herein to modulate activity of the PTTG polypeptidein living animals, in humans, or in biological tissues or fluidsisolated therefrom. Accordingly, compositions comprising a carrier andan amount of an antibody having specificity for PTTG polypeptideeffective to block naturally occurring ligands or other PTTG-bindingproteins from binding to invention PTTG polypeptide are contemplatedherein. For example, a monoclonal antibody directed to an epitope ofPTTG polypeptide molecules present on the surface of a cell and havingan amino acid sequence substantially the same as an amino acid sequencefor a cell surface epitope of a PTTG polypeptide including the aminoacid sequence shown in SEQ ID NOS:2, 4, 9, 14, 16, or 17 can be usefulfor this purpose.

[0145] The present invention also relates to transfected, transduced, orotherwise transformed mammalian host cells comprising any of theinventive PTTG-C-related polynucleotide-containing compositions asdescribed herein above. The inventive cells are either contained in amammalian subject or are cultured in vitro. Included among preferredembodiments are mammalian host cells containing an expression vectorcomprising the inventive PTTG-C-related polynucleotide in atranscriptional unit. Preferably, a product is expressed by the cell,which product, most preferably, but not necessarily, is a biologicallyactive PTTG-C peptide that functions to downregulate PTTG-mediatedneoplastic cellular proliferation and/or transformation. In vitro and invivo methods of transfecting, transducing, or transforming suitable hostcells are generally known in the art. Methods for culturing cells, invitro, are also well known. Exemplary methods of transfection,transduction, or transformation include, e.g., infection employing viralvectors (see, e.g., U.S. Pat. Nos. 4,405,712 and 4,650,764), calciumphosphate transfection (U.S. Pat. Nos. 4,399,216 and 4,634,665), dextransulfate transfection, electroporation, lipofection (see, e.g., U.S. Pat.Nos. 4,394,448 and 4,619,794), cytofection, microparticle bombardment,and the like. The heterologous nucleic acid can optionally includesequences which allow for its extrachromosomal (i.e., episomal)maintenance, or heterologous DNA can be caused to integrate into thegenome of the host (as an alternative means to ensure stable maintenancein the host cell).

[0146] The present invention further provides transgenic non-humanmammals containing the inventive mammalian cells that are capable ofexpressing exogenous nucleic acids encoding PTTG polypeptides,particularly the inventive PTTG-C peptides and functional fragmentsthereof as described hereinabove. As employed herein, the phrase“exogenous nucleic acid” refers to nucleic acid sequence which is notnative to the host, or which is present in the host in other than itsnative environment (e.g., as part of a genetically engineered DNAconstruct). Methods of producing transgenic non-human mammals are knownin the art. Typically, the pronuclei of fertilized eggs aremicroinjected in vitro with foreign, i.e., xenogeneic or allogeneic DNAor hybrid DNA molecules, and the microinjected fertilized eggs are thentransferred to the genital tract of a pseudopregnant female to gestateto term. (E.g., P. J. A. Krimpenfort et al., Transgenic mice depleted inmature T-cells and methods for making transgenic mice, U.S. Pat. Nos.5,175,384 and 5,434,340, P. J. A. Krimpenfort et al., Transgenic micedepleted in mature lymphocytic cell-type, U.S. Pat. No. 5,591,669).Alternatively, methods for producing transgenic non-human mammals caninvolve genetic modification of female or male germ cells using anexpression vector, which germ cells are then used to produce zygotes,which are gestated to term. The resulting offspring are selected for thedesired phenotype. These offspring can further be bred or cloned toproduce additonal generations of transgenic animals with the desiredphenotype. The inventive transgenic non-human mammals, preferably, butnot necessarily, are large animals such as bovines, ovines, porcines,equines, and the like, that produce relatively large quantities ofPTTG-C peptides that can be harvested for use in practicing the methodof inhibiting neoplastic cellular proliferation and/or transformation.

[0147] Most preferably, the transgenic non-human mammal is a female thatproduces milk into which the inventive PTTG-C peptides have beensecreted. The PTTG-C peptides are then purified from the milk. (E.g.,Christa, L., el al., High expression of the humanhepatocarcinoma-intestine-pancreas/pancreatic-associated protein(HIPPAP) gene in the mammary gland of lactating transgenic micesecretion into the milk and purification of the HIP/PAP lectin, Eur. J.Biochem. 267(6):1665-71 [2000]; Sobolev, A. S. et al., Receptor-mediatedtransfection of murine and ovine mammary glands in vivo, J. Biol. Chem.273(14):7928-33 [1998]; Zhang, K. et al., Construction of mammarygland-specific expression vectors for human clottingfactor IX and itssecretory expression in goat milk, Chin. J. Biotechnol. 13(4):271-6[1997]; Clark, A. J., Gene expression in the mammary glands oftransgenic animals, Biochem. Soc. Symp. 63:133-40 [1998]; Niemann, H. etal., Expression of human blood clotting factor VIII in the mammary glandof transgenic sheep, Transgenic Res. 8(3):237-47 [1999]).

[0148] Techniques for obtaining the preferred transgenic female mammalstypically employ transfection with an expression vector in which, withina transcriptional unit regulated, for example, by a suitableβ-lactoglobulin promoter, the PTTG-C peptide-encoding polynucleotide ischimerically linked with a polynucleotide encoding a mammary secretorysignal peptide, such that mammary-specific expression yields a chimericpolypeptide from which the desired PTTG-C peptide segment is removedproteolytically and purified.

[0149] The present invention is also directed to a kit for the treatmentof neoplastic cellular proliferation. The kit is useful for practicingthe inventive method of inhibiting neoplastic cellular proliferationand/or transformation. The kit is an assemblage of materials orcomponents, including at least one of the inventive compositionscontaining a PTTG-C-related polynucleotide and/or PTTG-C peptides, asdescribed above. The exact nature of the components configured in theinventive kit depends on its intended purpose. For example, someembodiments of the kit are configured for the purpose of treatingcultured mammalian cells. Other embodiments are configured for thepurpose of treating mammalian cells in vivo, i.e., for treatingmammalian subjects in need of treatment, for example, subjects withmalignant tumors. In a most preferred embodiment, the kit is configuredparticularly for the purpose of treating human subjects.

[0150] Instructions for use are also included in the kit. “Instructionsfor use” typically include a tangible expression describing the reagentconcentration or at least one assay method parameter, such as therelative amounts of reagent and sample to be admixed, maintenance timeperiods for reagent/sample admixtures, temperature, buffer conditions,and the like, typically for an intended purpose.

[0151] Optionally, the kit also contains other useful components, suchas, diluents, buffers, pharmaceutically acceptable carriers, specimencontainers, syringes, stents, catheters, pipetting or measuring tools,paraphernalia for concentrating, sedimenting, or fractionating samples,or the inventive antibodies, and/or primers and/or probes for controls.

[0152] The materials or components assembled in the kit can be providedto the practitioner stored in any convenient and suitable ways thatpreserve their operability and utility. For example the components canbe in dissolved, dehydrated, or lyophilized form; they can be providedat room, refrigerated or frozen temperatures.

[0153] The components are typically contained in suitable packagingmaterial(s). As employed herein, the phrase “packaging material” refersto one or more physical structures used to house the contents of thekit, such as invention nucleic acid probes or primers, and the like. Thepackaging material is constructed by well known methods, preferably toprovide a sterile, contaminant-free environment.

[0154] The packaging materials employed in the kit are those customarilyutilized in polynucleotide-based or peptide-based systems. As usedherein, the term “package” refers to a suitable solid matrix or materialsuch as glass, plastic, paper, foil, and the like, capable of holdingthe individual kit components. Thus, for example, a package can be aglass vial used to contain suitable quantities of an inventivecomposition containing nucleic acid or peptide components. The packagingmaterial generally has an external label which indicates the contentsand/or purpose of the kit and/or its components.

[0155] The invention will now be described in greater detail byreference to the following non-limiting examples, which unless otherwisestated were performed using standard procedures, as described, forexample in Maniatis et al., Molecular Cloning: A Laboratory Manual, ColdSpring Harbor Laboratory Press, Cold Spring Harbor, N.Y., USA (1982);Sambrook et al., Molecular Cloning: A Laboratory Manual (2 ed), ColdSpring Harbor Laboratory Press, Cold Spring Harbor, N.Y., USA (1989);Davis et al., Basic Methods in Molecular Biology, Elsevier SciencePublishing, Inc., New York, USA (1986); or Methods in Enzymology: Guideto Molecular Cloning Techniques Vol.152, S. L. Berger and A. R. KimmerlEds., Academic Press Inc., San Diego, USA (1987).

EXAMPLES Example 1 Isolation of PTTG cDNA

[0156] To clarify the molecular mechanisms involved in pituitarytumorigenesis, differential display PCR was used to identify mRNAsdifferentially expressed in pituitary tumor cells (see, e.g., Risingeret al., 1994, Molec. Carcinogenesis, 11:13-18; and Qu et al., 1996,Nature, 380:243-247). GC and GH₄ pituitary tumor cell lines (ATCC#CCL-82 and #CCL-82.1, respectively) and an osteogenic sarcoma cell lineUM108 (ATCC #CRL-1663) were grown in DMEM supplemented with 10% fetalbovine serum. Normal Sprague-Dawley rat pituitaries were freshlyexcised. Total RNA was extracted from tissue cultured cells andpituitary tissue using RNeaSy™ kit (Qiagen) according to manufacturer'sinstructions. Trace DNA contamination in RNA preparations was removed byDNase1 (GenHunter Corporation) digestion. cDNA was synthesized from 200ng total RNA using MMLV reverse transcriptase (GenHunter Corporation),and one of the three anchored primers (GenHunter Corporation). The cDNAgenerated was used in the PCR display.

[0157] Three downstream anchored primers AAGCT₁₁N (SEQ. ID. NO.:13,where N may be A, G, or C), were used in conjunction with 40 upstreamarbitrary primers for PCR display. 120 primer pairs were used to screenmRNA expression in pituitary tumors versus normal pituitary. One tenthof the cDNA generated from the reverse transcriptase reaction wasamplified using AmpliTaq DNA polymerase (Perkin Elmer) in a total volumeof 20 μl containing 10 mM Tris, pH 8, 4, 50 nM KCl, 1.5 mM MgCl₂, 0.001%gelatin, 2 μM dNTPs, 0.2 μM each primer and I Pl [³⁵S]dATP. PCR cyclesconsisted of 30 seconds at 94° C., 2 minutes at 40° C., and 30 secondsat 72° C. for 40 cycles. The products were separated on 6% sequencinggels, and dried gels were exposed to Kodak film for 24 to 48 hours.

[0158] After development, DNA fragments amplified from pituitary tumorand normal pituitary were compared. Bands unique to pituitary tumor wereexcised from the gel, and DNA extracted by boiling in 100 μl water andprecipitated with ethanol in the presence of glycogen (GenHunterCorporation). DNA was reamplified using the original set of primers andthe same thermal cycling conditions except that the dNTP concentrationwas increased to 20 μM. Reaction products were run on 1% agarose gel andstained with ethidium bromide. Bands were excised from the gel, eluted(Qiagen), cloned in to TA vectors (Invitrogen) and sequenced usingsequenase (USB). Using 120 primer pairs in the above-described PCRassay, 11 DNA bands that appeared to be differentially expressed inpituitary tumor cells were identified. These bands were evaluatedfurther by Northern blot analysis, using the PCR products as probes.

[0159] For Northern blot analysis, 20 μg of total RNA were fractionatedon 1% agarose gel, blotted on to nylon membrane and hybridized withrandom primed probe using Quickhyb solutions (Stratagene). Afterwashing, membranes were exposed to Kodak films for 6 to 72 hours. As aresult of the Northern blot assay, pituitary tumor specific signals weredetected for 2 bands. DNA sequence analysis revealed that one sequencewas homologous with Insulin-induced growth response protein, while theanother 396 base pair fragment (amplified using 5′-AAGCTTTTTTTTTTTG-3′[SEQ. ID. NO.:11] as the anchored primer and 5′-AAGCTTGCTGCTC-3′ [SEQID. NO.:12] as an arbitrary primer) showed no homology to knownsequences in the GenBank. This 396 bp fragment detected a highlyexpressed mRNA of about 1.3 kb in pituitary tumor cells, but not innormal pituitary nor in osteogenic sarcoma cells.

Example 2 Characterization of cDNA Sequence Encoding PTTG

[0160] To characterize this pituitary tumor-specific mRNA further, acDNA library was constructed using mRNA isolated from rat pituitarytumor cells. Poly A+RNA was isolated from pituitary tumor GH₄ cellsusing messenger RNA isolation kit (Stratagene) according tomanufacturer's instructions, and was used to construct a cDNA library inZAP Express vectors (Stratagene). The cDNA library was constructed usingZAP Express™ cDNA synthesis and Gigapack III gold cloning kit(Stratagene) following manufacturer's instructions. The library wasscreened using the 396 bp differentially displayed PCR product (clonedinto TA vector) as the probe. After tertiary screening, positive cloneswere excised by in vivo excision using helper phage. The resultingpBK-CMV phagemid containing the insert was identified by SouthernBlotting analysis. Unidirectional nested deletions were made into theDNA insert using EXOIII/Mung bean nuclease deletion kit (Stratagene)following manufacturer's instructions. Both strands of the insert DNAwere sequenced using Sequenase (USB).

[0161] Using the 396 bp PCR fragment described in Example 1 as a probe,a cDNA clone of 974 bp (SEQ. ID. NO.:1) was isolated and characterized.This cDNA was designated as pituitary tumor-specific gene (PTTG). Thesequence of PTTG contains an open reading frame for 199 amino acids (SEQID NO:2). The presence of an in-frame stop codon upstream of thepredicted initiation codon indicates that PTTG contains the completeORF. This was verified by demonstrating both in vitro transcription andin vitro translation of the gene product as described in Example 3.

Example 3 In vitro Transcription and Translation of the PTTG

[0162] Sense and antisense PTTG mRNAs were in vitro transcribed using T3and T7 RNA polymerase (Stratagene), respectively. The excess templatewas removed by DNase I digestion. The in vitro transcribed mRNA wastranslated in rabbit reticular lysate (Stratagene). Reactions werecarried out at 30° C. for 60 minutes, in a total volume of 25 μlcontaining 3 μl in vitro transcribed RNA, 2 μl ³⁵S-Methionine (Dupond)and 20 μl lysate. Translation products were analyzed by SDS-PAGE (15%resolving gel and 5% stacking gel), and exposed to Kodak film for 16hours.

[0163] The results indicate that translation of in vitro transcribedPTTG sense mRNA results in a protein of approximately 25 KD on SDS-PAGE,whereas no protein was generated in either the reaction without addedmRNA or when PTTG antisense mRNA was utilized.

Example 4 Northern Blot Analysis of PTTG mRNA Expression

[0164] A search of GenBank and a protein profile analysis (using a BLASTProgram search of databases of the national center for BiotechnologyInformation) indicated that PTTG shares no homology with knownsequences, and its encoded protein is highly hydrophilic, and containsno well recognized functional motifs. The tissue expression patten ofPTTG mRNA was studied by Northern Blot analysis. A rat multiple tissueNorthern blot was purchased from Clontech. Approximately 2 μg of polyA+RNA per lane from eight different rat tissues (heart, brain, spleen,lung, liver, skeletal muscle, kidney, and testis) was run on adenaturing formaldehyde 1.2% agarose gel, transferred to nylon membraneand UV-cross linked. The membrane was first hybridized to the fulllength PTTG cDNA probe, and was stripped and rehybridized to a humanβ-actin cDNA control probe. Hybridization was performed at 60° C. forone hour in ExpressHyb hybridization solution (Clontech). Washing wastwice 15 minutes at room temperature in 2×SSC, 0.05%SDS, and twice 15minutes at 50° C. in 0.1%SSC, 0.1%SDS. Exposure time for PTTG probe was24 hrs, and actin probe 2 hours.

[0165] The results of the Northern assay indicate that testis is theonly tissue, other than pituitary tumor cells, that expresses PTTG mRNA,and the testis expression level is much lower (2 μg polyA+ mRNA, 24 hourexposure) than in pituitary tumor cells (20 μg total RNA, 6 hourexposure). Interestingly, the testicular transcript (about 1 Kb) isshorter than the transcript in pituitary tumors (1.3 Kb), indicatingthat the mRNA is differentially spliced in testis, and that the 1.3 Kbtranscript is specific for pituitary tumor cells.

Example 5 Over-Expression of PTTG in NIH 3T3 Fibroblast Cells

[0166] Since PTTG mRNA is over-expressed in pituitary tumor cells,whether this protein exerts an effect on cell proliferation andtransformation was determined. An eukaryotic expression vectorcontaining the entire coding region of PTTG was stably transfected intoNIH 3T3 fibroblasts.

[0167] The entire coding region of the PTTG was cloned in frame intopBK-CMV eukaryotic expression vector (Stratagene), and transfected intoNIH 3T3 cells by calcium precipitation. 48 hrs after transfection, cellswere diluted 1:10 and grown in selection medium containing 1 mg/ml G418for two weeks in when individual clones were isolated. Cell extractswere prepared from each colony and separated on 15% SDS-polyacrylamidegels, and blotted onto nylon membrane. A polyclonal antibody wasgenerated using the first 17 amino acids of PTTG as epitope (ResearchGenetics). The antibody was diluted 1:5000 and incubated with the abovemembrane at room temperature for 1 hour. After washing, the membrane wasincubated with horseradish peroxidase-labeled secondary antibody for onehour at room temperature. The hybridization signal was detected byenhanced chemiluminescence (ECL detection system, Amersham).

[0168] Expression levels of the PTTG were monitored by immunoblotanalysis using the above-described specific polyclonal antibody directedagainst the first 17 amino acids of the protein. Expression levels ofindividual clones varied, and clones that expressed higher proteinlevels were used for further analysis.

Example 6 Effect of PTTG Expression on Cell Proliferation

[0169] A non-radioactive cell proliferation assay was used to determinethe effect of PTTG protein over-expression on cell proliferation (see,e.g., Mosmann, T., 1983, J. Immunol. Meth., 65:55-63; and Carmichael etal., 1987, Cancer Res., 47:943-946). Cell proliferation was assayedusing CellTiter 96TM Non-radioactive cell proliferation assay kit(Promega) according to the manufacturer's instructions. Five thousandcells were seeded in 96 well plates (6 wells for each clone in eachassay), and incubated at 37° C. for 24 to 72 hours. At each time point,15 μl of the Dye solution were added to each well, and incubated at 37°C. for 4 hours. One hundred μl of the solubilization/stop solution werethen added to each well. After one hour incubation, the contents of thewells were mixed, and absorbance at 595 nm was recorded using an ELISAreader. Absorbance at 595 nm correlates directly with the number ofcells in each well.

[0170] Three independent experiments were performed. The cell growthrate of 3T3 cells expressing PTTG protein (assayed by cellularconversion of tetrazolium into formazan) was suppressed 25 to 50% ascompared with 3T3 cells expressing the pCMV vector alone, indicatingthat PTTG protein inhibits cell proliferation (data not shown).

Example 7 PTTG Induction of Morphological Transformation and Soft-AgarGrowth of NIH 3T3 Cells

[0171] The transforming property of PTTG protein was demonstrated by itsability to form foci in manslayer cultures and showanchorage-independent growth in soft agar (Table 1). As primarypituitary cells are an admixture of multiple cell types and they do notreplicate in vitro, NIH 3T3 cells were employed. For the soft agar assay(Schwab et al., 1985, Nature, 316:160-162), 60 mM tissue culture plateswere coated with 5 ml soft-agar (20% 2×DEEM, 50% DEEM, 10% fetal bovineserum, 20% 2.5% agar, melted and combined at 45° C.). 2 ml cellssuspended in medium were then combined with 4 ml agar mixture, and 1.5ml of this mixture added to each plate. Cells were plated at a densityof 10⁴ cells/dish and incubated for 14 days before counting the numberof colonies and photography. Only colonies consisting of at least 40cells were counted. Values shown in Table 13 are means±SEM oftriplicates. TABLE 13 Colony Formation by NIH 3T3 Cells Transfected withPTTG cDNA Constructs Efficiency of Colony Cell line Growth in Soft Agarformation in Soft Agar (%)* No DNA 0 0 Vector only 1.3 ± 0.7 0.013 PTTG3  26 ± 4.6 0.26 PTTG 4 132 ± 26  1.32 PTTG 8  33 ± 6.0 0.33 PTTG 9 72 ±13 0.72 PTTG 10 92 ± 18 0.92

[0172] The results indicate that NIH 3T3 parental cells and 3T3 cellstransfected with pCMV vector do not form colonies on soft agar, whereas3T3 cells transfected with PTTG form large colonies. In addition, focaltransformation is observed in cells over-expressing PTTG protein, butcells expressing pCMV vector without the PTTG insert showed similarmorphology to the parental 3T3 cells.

Example 8 Assay to Determine Whether PTTG is Tumorigenic in vivo

[0173] To determine whether PTTG is tumorigenic in vivo,PTTG-transfected 3T3 cells were injected subcutaneously into athymicnude mice. 3×10⁵ cells of either PTTG or pCMV vector -only transfectedcells were resuspended in PBS and injected subcutaneously into nude mice(5 for each group). Tumors were excised from sacrificed animals at theend of the 3rd week and weighed. All injected animals developed largetumors (1-3 grams) within 3 weeks. The results are shown in Table 14below. No mouse injected with vector-only transfected cells developedtumors. These results clearly indicate that PTTG is a potenttransforming gene in vivo. TABLE 14 In vivo Tumorigenesis by NIH 3T3Cells Transfected with PTTG cDNA Expression Vector Cell line No. Animalsinjected Tumor formation Vector only 5 0/5 PTTG 4 5 5/5

Example 9 Human Carcinoma Cell Lines Express PTTG

[0174] The pattern of expression of PTTG in various human cell lines wasstudied employing a multiple human cancer cell line Northern blot(Clontech). The specific cell lines tested are shown in Table 15 below.TABLE 15 Human Carcinoma Cell Lines Tested Cell Line PTTG Expression 1Promyelocytic Leukemia HL-60 + 2 HeLa Cell S3 + 3 Chronic MyelogenousLeukemia K-562 + 4 Lymphoblastic Leukemia MOLT-4 + 5 Burkitt's lymphomaRaji + 6 Colorectal Adenocarcinoma SW 480 + 7 Lung Carcinoma A549 + 8Melanoma G361 +

[0175] About 2 μg polyA RNA from each of the 8 cell lines indicated inTable 3 above were placed on each lane of a denaturing formaldehyde 1.2%agarose gel, separated by denaturing gel electrophoresis to ensureintactness, transferred to a charge-modified nylon membrane by Northernblotting, and fixed by UV irradiation. Lanes 1 to 8 contained RNA frompromyelocytic leukemia HL-60, HeLa cell line S3, human chronicmyelogenous leukemia K-562, lymphoblastic leukemia MOLT-4, Burkitt'slymphoma Raji, colorectal adenocarcinoma SW 480, lung carcinoma A549 andmelanoma G361, respectively RNA size marker lines at 9.5, 7.5, 4.4, 2.4,and 1.35 kb were indicated in ink on the left margin of the blot, andutilized as sizing standards, and a notch was cut out from the lowerleft hand corner of the membrane to provide orientation. Radiolabeledhuman β-actin cDNA was utilized as a control probe for matching ofdifferent batches of polyA RNAs. A single control band at 2.0 kb in alllanes spotted is confirmatory.

[0176] The blots were probed with the full length rat PTTG cDNA probe(SEQ. ID No:1; 974 bp) at 60° C. for 1 hr. in ExpressHyb hybridizationsolution (Clontech) as described by Sambrook et al., the relevantsection of which reference is incorporated herein by reference. See,Sambrook et al., Molecular Cloning: A Laboratory Manual, 2nd. Ed, ColdSpring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (1989) Theblots were then washed twice for 15 min at room temperature in 2×SSC,0.05% SDS, and twice for 15 min at 50° C. in 0.1% SSC, 0.1% SDS. A moredetailed description of the remaining experimental procedures masy befound in Pei & Melmed, the relevant section of which is incorporatedherein by reference. (See, Pei & Melmed, Endocrinology 4: 433-441[1997]).

[0177] All cells tested by the Northern blot analysis as described aboveevidenced expression of human PTTG (i.e., PTTG1), including lymphoma,leukemia, melanoma and lung carcinomas, among others.

Example 10 Molecular Cloning of Human PTTG cDNA

[0178] A human fetal liver cDNA library (Clontech, Palo Alto, Calif.)was screened as described by Maniatis et al. (Maniatis et al., Molecularcloning, Cold Spring Harbor Press, 1989), using a radioactively labeledcDNA fragment of the entire rat PTTG coding region as a probe. The cDNAinserts from positive clones were subcloned into plasmid pBluescript-SK(Stratagene, La Jolla, Calif.), and subjected to sequence analysis usingSequenase kit (U S. Biochemical Corp., Cleveland, Ohio).

[0179] A complete open reading frame containing 606 bp was found in thepositive clones. The homology between the nucleotide sequences of theopen reading frame and the coding region of rat PTTG is 85%. Amino acidsequence comparison between the translated product of this open readingframe and rat PTTG protein reveals 77% identity and 89% homology. ThecDNAs obtained from these clones represents human homologies of ratPTTG. No other cDNA fragments with higher homology were detected fromthe library.

Example 11 Tissue Distribution of Human PTTG mRNA

[0180] Total RNA was prepared using Trizol Reagent (Gibco-BRL,Gaithersburg, Md.) from normal human pituitary glands (Zoion ResearchInc. Worcester, Mass.) and fresh human pituitary tumors collected atsurgery and frozen in liquid nitrogen. 20 mg total RNA were used for 1%agarose gel electrophoresis. RNA blots (Clontech, Palo Alto, Calif.)derived from normal adult and fetal tissues as well as from malignanttumor cell lines, were hybridized with radioactively labeled human cDNAfragment containing the complete coding region. The RNA isolated fromeach cell line was transferred onto a nylon membrane (Amersham,Arlington Heights, Ill.), and hybridized with radioactively labeledprobe at 55° C. overnight in 6×SSC, 2×Denhardt's solution, 0.25% SDS.The membranes were washed twice at room temperature for 15 minutes each,and then for 20 minutes at 60° C. in 0.5×SSC, 0.1% SDS, andautoradiographed. The autoradiography was carried out using KodakBIOMEX-MR film (Eastman Kodak, Rochester, N.Y.) with an intensifyingscreen. The blots were stripped by washing for 20 minutes in distilledwater at 95° C. for subsequent probing.

[0181] The results from the Northern blot analysis indicated that PTTGis expressed in liver, but not in brain, lung, and kidney of human fetaltissue. In addition, PTTG is strongly expressed in testis, modestlyexpressed in thymus, and weakly expressed in colon and small intestineof normasl human adult tissue. No expression was detected by Northernanalysis in brain, heart, liver, lung, muscle, ovary, placenta, kidney,and pancreas.

[0182] The expression of PTTG in several human carcinoma cell lines wasalso analyzed by Northern blots. In every carcinoma cells examined, PTTGwas found highly expressed. The human tumor cell lines tested are listedin Table 16 below. TABLE 16 Tested Human Tumor Cell Lines Promyelocyticleukemia HL-60 Epitheloid carcinoma HeLa cell S3 Chronic myelogenousleukemia K-562 Lymphoblastic leukemia MOLT-4 Burkitt's lymphoma RajiColorectal adenocarcinoma SW 480 Lung carcinoma A549 Melanoma G361Hepatocellular carcinoma Hep 3B Thyroid carcinoma TC-1 Breastadenocarcinoma MCF-7 Osteogenic sarcoma U2 OS Placenta choriocarcinomaJAR Choriocarcinoma JEG-3

Example 12 Human PTTG Expression in Normal Pituitary and PituitaryTumors

[0183] RT-PCR was performed as follows. 5 mg total RNA were treated with100 U RNase-free DNase I at room temperature for 15 minutes. DNase I wasinactivated by incubation at 65° C. for 15 minutes. The sample was thenused for reverse transcription using oligo-dT primer and SuperScript IIreverse transcriptase (Gibco-BRL, Gaithersburg, Md.). After reversetranscription, the sample was subjected to PCR amplification with PCRSuperMix (Gibco-BRL, Gaithersburg, Md.) using hPTTG-specific primers andhuman cyclophilin A-specific primers as an internal control.

[0184] Northern blot analysis indicated that the level of expression ofPTTG is quite low in normal pituitary as well as in pituitary tumors.Therefore, comparative RT-PCR was used to study the expression of PTTGquantitatively in normal pituitary and pituitary tumors. The results ofthis study showed that in most of pituitary tumors tested, includingnon-functioning tumors, GH-secreting tumors, and prolactinomas, theexpression level of PTTG was higher than that of normal pituitary.

Example 13 Stable Transfection of Human PTTG into NIH 3T3 Cells

[0185] The complete coding region of hPTTG cDNA was subcloned in readingframe into the mammalian expression vector pBK-CMV (Stratagene, LaJolla, Calif.), and transfected into NIH 3T3 fibroblast cells byLipofectamine (Gibco-BRL, Gaithersburg, Md.) according to manufacturer'sprotocol. 24 hours after transfection, the cells were serially dilutedand grown in selection medium containing 1 mg/ml G418 for 2 weeks.Individual clones were isolated and maintained in selection medium.Total RNA was isolated from hPTTG-transfected cell lines as well as fromcontrol cells in which blank vector pBK-CMV had been transfectedNorthern blot was performed to confirm overexpression of hPTTG intransfected cell lines. These cell lines were used in subsequent cellproliferation assay as well as in vitro and in vivo transformationassay.

Example 14 Cell Proliferation Assay

[0186] A cell proliferation assay was performed using the CellTiter 96non-radioactive cell proliferation assay kit (Promega Medicine, WI)according to the manufacturer's protocol 5,000 cells were seeded in96-well plates and incubated at 37° C. for 24-72 hours. Eight wells wereused for each clone in each assay. At each time point, 15 ml of dyesolution was added to each well and the cells were incubated at 37° C.for 4 hours. After incubation, 100 ml solubilization/stop solution wereadded to each well, and the plates incubated overnight at roomtemperature. The absorbance was determined at 595 nm using an ELISAplate reader.

[0187] Control and hPTTG-overexpressing NIH 3T3 cells were used toperform this assay. The results indicated that the growth of cellstransfected with the PTTG-expressing vector was suppressed by 30˜45% ascompared with cells transfected with blank vector. These results clearlyshow that the PTTG protein inhibits cell proliferation.

Example 15 In vitro and in vivo Transformation Assay

[0188] (a) In vitro Transformation Assay

[0189] Control and hPTTG-transfected cells were tested foranchorage-independent growth in soft agar; 3 ml of soft agar (20% of2×DMEM, 50% DMEM, 10% fetal bovine serum, and 20% of 2.5% agar, meltedand mixed at 45° C.) were added to 35-mm tissue dishes. 10,000 cellswere mixed with 1 ml soft agar and added to each dish, and incubated for2 weeks until colonies could be counted and photographed.

[0190] (b) In vivo Transformation Assay

[0191] 5×10⁵ cells containing either ablank vector or hPTTG-expressingcells were injected into nude mice. The mice were sacrificed two weeksafter injection, and the tumors formed near the injection sitesexamined.

[0192] When the NIH 3T3 cells stably transfected with thePTTG-expressing vector were tested in an anchorage-independent growthassay, these cells caused large colony formation on soft agar,suggesting the transforming ability of PTTG protein.

[0193] When the NIH 3T3 cells were injected into nude mice, they causedin vivo tumor formation within 2 weeks after injection. These dataindicate that human PTTG, as its rat homologue, is a potent transforminggene.

Example 16 Inhibition of Cell Transformation/Tumor formation by PTTGC-Terminal Polypeptide

[0194] Cell lines. NIH 3T3 cells were maintained in high glucose (4.5g/L) DMEM (Gibco-BRL) supplemented with 10% fetal bovine serum. HeLacells were maintained in low glucose (1 g/L) DMEM (Gibco-BRL)supplemented with 10% fetal bovine serum (FBS). T-47D and MCF-7 cellswere maintained in high glucose DMEM (Gibco-BRL) supplemented with 10%fetal bovine serum and 0.01 mg/mL bovine insulin (Sigma). All cell lineswere obtained from American Type Culture Collection (ATCC).

[0195] Site-directed mutagenesis and stable transfection of human andmutant PTTG into NIH 3T3 cells. Point mutations on the proline-richdomain(s) of wild type human PTTG polypeptide (wtPTTG) were generated byPCR-based site-directed mutagenesis. Two synthetic oligonucleotides,5′-GATGCTCTCCGCACTCTGGGAATCCAATCTG-3′ (SEQ. ID. NO.:5) and5′-TTCACAAGTTGAGGGGCGCCCAGCTGAAACAG-3′ (SEQ. ID. NO.:6), which causepoint mutations that result in amino acid sequence changes P163 A, S165Q, P166L, P170L, P172A, and P173L in the wtPTTG protein, were used toamplify human PTTG cDNA cloned into pBlue-Script-SK vector (Stratagene).Amplified mutated cDNA (mutPTTG) was then cloned into mammalianexpression vector pCI-neo (Promega). Overexpression of mutPTTG intransfected cells was confirmed by Northern analysis and RT-PCR followedby direct sequence analysis. wtPTTG and mutPTTG were subcloned intopCI-neo, and the vector was used to transfect NIH 3T3 cells as describedin Zhang, X., et al. [1999a].

[0196] Transactivation assay. wtPTTG CDNA was fused in frame with pGAL4(Stratagene), designated pGAL4-wtPTTG and was used as template fordeletion and mutation analysis; mutPTTG cDNA was also fused in framewith pGAL4 and designated pGAL4-mutPTTG pGAL4-VP16 was used as apositive control. Experimental plasmids; were co-transfected with pLUCand pCMV-β-Gal (as internal control). Cell lysates were prepared 48hours after transfection and assayed for luciferase activity asdescribed (Wang, Z. and Melmed, S. [2000]; Sambrook, J., et al.,Molecular Cloning: A Laboratory Manual, 2d Ed. Cold Spring HarborLaboratory, Cold Spring Harbor, N.Y., 10.2.1-10.2.6[1989]).

[0197] Constructions of expression vectors for wild type and mutanthuman PTTG C-terminal polypeptides. To generate wtPTTG and mutPTTGC-terminal polypeptide expression vector, the internai Xba I site ofwtPTTG and mutPTTG cDNA and the 3′-portions of these cDNAs were clonedinto pCI-neo (Promega, Madison, Wis.) via XbaI and NotI sites. In theseclone, the ATG for M147 of full-length PTTG is used as an initiationcodon, generating a polypeptide of 56 amino acid residues correspondingto nucleotide positions 147 through 202 of full-length wtPTTG.

[0198] Stable transfection of human PTTG C-terminal peptide into tumorcells. Wild type and mutant PTTG C-terminal expression constructs weretransfected into HeLa, MCF-7, and T47-D cells with Lipofectin(GIBCO-BRL) according to the manufacturer's protocol. Twenty-four hoursafter transfection, cells were serially diluted and selected with G418(1 mg/mL) for 2 weeks. Individual clones were isolated and maintained inselection medium (respective high or low glucose DMEM with 10% FBS, asdescribed above, and G148 [1 mg/mL]), and total RNA was extracted fromtransfected cells. Expression of wild-type and mutated PTTG-C terminalwas confirmed by RT-PCRusing two synthetic oligonucleotides, with onespecific to the 5′-nontranslational region from vector pCI-neo,5′-GGCTAGAGTACTTAATACGACTCACTATAGGC-3′ (SEQ. ID. NO.:7), and the otherto the 3′-translational region of PTTG1 cDNA,5′-CTATGTCACAGCAAACAGGTGGCAATTCAAC-3′ (SEQ. ID. NO:8), followed bydirect sequence analysis.

[0199] In vitro colony formation and in vivo tumorigenesis. NIH 3T3stable transfectants were tested in vivo as described in Zhang, X., etal. [1999a]. Transfected cells were tested for anchorage-independentgrowth in soft agar as described Zhang, X., et al. [1999a]. HeLa cellswere incubated for 3 weeks and MCF-7 and T-47D cells for 2 weeks. For invivo assays of tumorigenesis, 1×10⁷ MCF-7 stable transfectants wereresuspended in 500 μL MATRIGEL basement membrane matrix (BectonDickinson, Bedford, Mass.) and were injected subcutaneously into nudemice (three mice for each group). After four weeks, animals werephotographed and tumors were excised and weighed.

[0200] ELISA of basic fibroblast growth factor (bFGF) in conditionedmedium. The concentration of basic fibroblast growth factor (bFGF)concentration in HeLa cell culture medium was assayed using QuantikineHS Human FGF Basic Immunoassay Kit (R&D Systems, Minneapolis, Minn.)according to the manufacturer's protocol. Cells (1×10⁵) were plated in100-mm cell culture dishes. After 72 hours, the culture medium wascollected and 200 mL was used for ELISA assay.

[0201] Effects of wild type human PTTG and mutant PTTG overexpression ontumor induction. It was previously demonstrated that NIH 3T3 cellsoverexpressing wild type PTTG formed large colonies in ananchorage-independent growth assay and formed tumors when injected intoathymic nude mice, while point mutations in the proline-rich region (P163 A, P 170L, P 172A, and P173L) abrogated formation of colonies andtumors (Zhang, X., et al. [1999a]). Overexpression of wtPTTG and mutPTTG(P163A, S165Q, P166L, P170L, P172A, and P173L) in each transfectant cellline was confirmed by Northern analysis and RT-PCR followed by directsequence analysis (not shown).

[0202] It was further shown that overexpressing PTTG transfectantsinjected into athymic nude mice caused tumor formation within 2 weeks inall injected animals. Five mice in each of three groups were injectedsubcutaneously with 3×10⁵ NIH 3T3 cells transfected with: (1) controlcell line (transfected with pGAL4 vector alone); (2) wild typePTTG-overexpressing (wtPTTG); or (3) mutant PTTG-overexpressing (mutPTTG[P163A, S 165Q, P166L, P170L, P172A, and P173L]). After 2 weeks, micewere sacrificed and tumors were excised and weighed. In the miceinjected with control transfectants or mutPTTG transfectants, no tumorsdeveloped. but mice injected with transfectant cells bearing wtPTTGdeveloped tumors without exception. Tumor weights ranged from 470 to1500 mg (Table 17). TABLE 17 Tumor formation by PTTG-expressing NIH 3T3Cells in Athymic Nude Mice. Tumor weight (mg) Vector wtPTTG mutPTTGnone* 1500  none none 770 none none 1250  none none 550 none none 470none

[0203] PTTG exhibits transcriptional activation. Vector pGal4 alone(negative control) did not activate the luciferase (luc) reporter, and aknown activation domain, VP16, significantly increased reporter activityabout 28-fold. pGAL4-wtPTTG exhibited transactivation properties andinduced reporter activity about 22-fold (FIG. 1).

[0204] Transcriptional activity of pGAL4-mutPTTG (mutated proline region[P163A, S165Q, P166L., P170L, P172A, and P173L]), other point mutations,as well as a separate deletions (d) of wtPTTG were also tested asindicated in Table 18. In Table 18, the indicated plasmids wereco-transfected with pLuc and pCMV-β-Gal into NIH 3T3 cells, andluciferase assays were performed, with P-Gal serving as the internalcontrol. Each value represents triplicate wells from two independentexperiments (±SEM); transactivation by wtPTTG was designated 100%.pGAL4-mutPTTG exhibited about 95% transactivating activity compared topGAL4-wtPTTG, thus confirming the importance of the wtPTTG proline-richmotif for transactivation. TABLE 18 Transactivation assay of hPTTGmutants. Mutant activation activity (%)(± SEM) pGAL4-wtPTTG 100 163 Pro→Ala 100 ± 10 166 Pro →Ala  45 ± 5* 170 Pro →Ala 100 ± 10 182 Pro →Ala100 ± 10 152 Glu →Gln 100 ± 10 192 Glu →Gln  50 ± 3* 165 Ser →Ala  30 ±3* 165 Ser →Leu  20 ± 2* 176 Ser →Ala 100 ± 10 183 Ser →Ala 100 ± 10 184Ser →Ala 100 ± 10 d(1-100) 100 ± 10 d(180-202) 100 ± 10 mutPTTG  6 ± 1*

[0205] Human PTTG C-terminal peptide expression blocks celltransformation. The critical role of the proline-rich region intransactivation, transformation and tumor formation, as described above,implies that PTTG functions through SH3-mediated signal transduction. Ifhuman PTTG1 protein mediates the SH3-related signal cascade, it probablycontains at least two functional domains interacting with upstream anddownstream signal molecule(s), respectively. A mutant protein containingonly one such functional domain could then act in a dominant-negativemanner to abrogate wild-type protein function and disrupt signaltransduction.

[0206] Based on this hypothesis, a truncated PTTG1 mutant peptide,lacking N-terminal amino acid residues 1-146, was introduced into humancarcinoma cells. An expression construct was used expressing a PTTG-Cpeptide corresponding to residues 147-202 of the full-length protein,under the control of a CMV promoter. This polypeptide contains theproline-rich domain(s) (residues 163-173; Zhang, X., et al. [1999a]),and when the coding sequence was fused to glutathione S-transferase(GST), it was expressed in Escherichia coli as an intact protein withthe appropriate molecular weight (data not shown). Mutant expressionvector pCIneo-mutPTTG (mutated proline region [P163A, S165Q, P166L.,P170L, P172A, and P173L]), as well as the empty vector pCI-neo alone ascontrol, were stably transfected into HeLa, MCF-7, and T-47D humancarcinoma cell lines.

[0207] Transfectants expressing wild-type PTTG carboxy-terminal peptide(PTTG-C), PTTG C-terminal mutated in several proline residues (PTTG-Cpm;mutated proline region [P163A, S165Q, P166L., P170L, P172A, andP173L]),andvector(V), wereisolated. Expression of each transfectant line wasconfirmed by RT-PCR, using a primer directed to the 5′-nontranslationalregion of the expression vector and a primer directed to the3′-translational region of PTTG mRNA, followed by direct sequenceanalysis (FIGS. 2A, 2B, and 2C). Transforming abilities of all three ofthese stably transfected cell lines were tested in ananchorage-independent growth assay, PTTG-Cpm cells were observed to formlarge colonies, as did control V cells containing the same expressionvector but lacking either wild type or mutant C-terminal polypeptide.Each transfectant cell line was plated in three different plates. HeLawas scored on the 21st day and T-47D and MCF-7 on the 14th day. Coloniesconsisting of 60 or more cells were scored. However, the number andsize, of colonies formed by cells expressing PTTG-C were markedlyreduced (p<0.01) (FIG. 3). Table 19 (below) summarizes the soft agarcolony formation for each cancer cell type. TABLE 19 Colony Formation byPTTG 1 C-terminal (PTTG-C) and mutant PTTG C-terminal (PTTG-Cpm)Expressing Cells in Soft Agar. Colonies/10⁴ Cells Cell Line Vector (mean± SEM) HeLa Vector alone 1465 ± 54 Vector alone 2392 ± 55 PTTG-C  11 ±2* PTTG-C   6 ± 1* PTTG-C  48 ± 3* PTTG-C   3 ± 1* PTTG-Cpm 1169 ± 77PTTG-Cpm 1097 ± 79 PITG-Cpm 2615 ± 76 T-47D Vector alone  135 ± 4 PTTG-C 46 ± 5* PTTG-C  52 ± 2* PTTG-Cpm  193 ± 5 PTTG-Cpm  106 ± 5 MCF-7Vector alone  287 ± 3 PTTG-C   9 ± 3* PTTG-C  34 ± 4* PTTG-Cpm  236 ± 11PTTG-Cpm  206 ± 4

[0208] Human PTTG C-terminal polypeptide-expressing MCF-7 cells fail todevelop tumors in vivo. Stably transfected MCF-7 cell lines wereinjected (1×10⁷ cells/per mouse in 500 μL MATRIGEL basement membranematrix) subcutaneously into athymic nude mice. After four weeks, micewere photographed, killed, and their tumors were excised and weighed.Three mice injected with cells transfected with control vector onlydeveloped visible tumors in 4 weeks, while three mice injected withPTTG-C-transfected cells failed to generate tumors. At autopsy, absenceof subcutaneous or other peripheral tumor formation was confirmed in themice receiving PTTG-C transfected cells. Three mice injected withPTTG-Cpm-transfected cells also developed tumors after 4 weeks, whichwere similar in size to those developed in mice injected with controlvector-transfected cells, indicating that the mutated PTTG-C-terminalpolypeptide lost its ability to abrogate endogenous PTTG function (Table20). TABLE 20 Tumor formation by PTTG-C expressing MCF-7 Cells inAthymic Nude Mice. Tumor weight (mg) Vector PTTG-C PTTG-Cpm 212 none*185 235 none 196 209 none 203

[0209] These results show that overexpression of the PTTG C-terminalpeptide caused cancer cells to lose their abilities for in vitro celltransformation and ex vivo tumor growth. Also, the importance ofproline-rich regions is further confirmed here, since PTTG C-terminalpeptide containing point mutations of.these proline residues failed tointerfere with transforming activity or tumor-forming activity in vivo.

[0210] Suppression of bFGF secretion and PRL expression by PTTG-Cpeptide. As cells expressing wild-type human PTTG-C terminal peptide hadmarkedly reduced colony forming ability on soft agar and were alsounable to induce solid tumor growth in vivo, expression of bFGF wastested in HeLa transfectants. An enzyme-linked immunoabsorbent assay(ELISA) was performed to examine bFGF levels in conditioned mediumderived from 72-hour cultures of HeLa transfectants. As shown in FIG. 4,bFGF levels were markedly decreased in conditioned medium derived fromPTTG-C DNA-transfected cells than those derived from vector-only andPTTG-Cpm-transfected cells, indicated a suppression of bFGF secretionresulting from the presence of PTTG carboxy-terminal peptide.

[0211] Since, the growth rate of solid tumors is directly related toactivation of angiogenesis and recruitment of new blood vessels, thisshows that, in accordance with the inventive method, the ability for newblood vessel growth can be impaired by the inventive PTTG-C peptides,providing an additional mechanism leading to the failure of in vivoneoplastic cellular proliferation and tumor growth. Experimental tumorsdo not grow more than 1 or 2 mm in diameter in the absence ofangiogenesis. (Folkman, J., N. Engl. J. Med. 285:1182-1186 [1971];Folkman, J., and Klagsburn, M. (1987) Science 235:442-447 [1987]). Thehuman cancer cell lines used in this study form prominent solid tumors(>2 mm in diameter) indicating active angiogenesis.

[0212] Moreover, these results imply that additional hormonal regulatorycascades can be affected by the inventive PTTG-C peptides, becausereduced bFGF secretion can result in altered expression of bFGF-mediatedpathways, for example prolactin (PRL) expression. For example,expression of the same human wild-type PTTG-C-terminal peptide (aminoacid residues 147-202 of SEQ. ID. NO.:4) in rat prolactin (PRL)- andgrowth hormone (GH)-secreting GH3 cells caused markedly reduced PRLpromoter activity (about 16-fold decrease), PRL mRNA expression (about10-fold decrease), and prolactin protein expression (about 72-folddecrease) in comparison to rat GH3 cells transfected with control vectoralone or GH3 cells expressing a mutated PTTG1 C-terminal fragment(P163A, S165Q, P166L, P170A, P172A, and P173L; data not shown).Furthermore, a compensatory increase in GH mRNA (about 13-fold increase)and protein (about 37-fold increase) were observed in thePTTG-C-terminal expressing GH3 cells. These observations demonstratethat PTTG carboxy-terminal peptide expressed in GH3 cells alters thehormonal secretory pattern by silencing PRL-gene expression andaugmenting GH expression.

1 19 1 974 DNA Rattus rattus 1 aattcggcac gagccaacct tgagcatctgatcctcttgg cttctccttc ctatcgctga 60 gctggtaggc tggagacagt tgtttgggtgccaacatcaa caaacgattt ctgtagttta 120 gcgtttatga ccctggcgtg aagatttaaggtctggatta agcctgttga cttctccagc 180 tacttctaaa tttttgtgca taggtgctctggtctctgtt gctgcttagt tcttccagcc 240 ttcctcaatg ccagttttat aatatgcaggtctctcccct cagtaatcca ggatggctac 300 tctgatcttt gttgataagg ataacgaagagccaggcagc cgtttggcat ctaaggatgg 360 attgaagctg ggctctggtg tcaaagccttagatgggaaa ttgcaggttt caacgccacg 420 agtcggcaaa gtgttcggtg ccccaggcttgcctaaagcc agcaggaagg ctctgggaac 480 tgtcaacaga gttactgaaa agccagtgaagagtagtaaa cccctgcaat cgaaacagcc 540 gactctgagt gtgaaaaaga tcaccgagaagtctactaag acacaaggct ctgctcctgc 600 tcctgatgat gcctacccag aaatagaaaagttcttcccc ttcgatcctc tagattttga 660 gagttttgac ctgcctgaag agcaccagatctcacttctc cccttgaatg gagtgcctct 720 catgatcctg aatgaagaga gggggcttgagaagctgctg cacctggacc ccccttcccc 780 tctgcagaag cccttcctac cgtgggaatctgatccgttg ccgtctcctc ccagcgccct 840 ctccgctctg gatgttgaat tgccgcctgtttgttacgat gcagatattt aaacgtctta 900 ctcctttata gtttatgtaa gttgtattaataaagcattt gtgtgtaaaa aaaaaaaaaa 960 aaactcgaga gtac 974 2 199 PRTRattus rattus 2 Met Ala Thr Leu Ile Phe Val Asp Lys Asp Asn Glu Glu ProGly Ser 1 5 10 15 Arg Leu Ala Ser Lys Asp Gly Leu Lys Leu Gly Ser GlyVal Lys Ala 20 25 30 Leu Asp Gly Lys Leu Gln Val Ser Thr Pro Arg Val GlyLys Val Phe 35 40 45 Gly Ala Pro Gly Leu Pro Lys Ala Ser Arg Lys Ala LeuGly Thr Val 50 55 60 Asn Arg Val Thr Glu Lys Pro Val Lys Ser Ser Lys ProLeu Gln Ser 65 70 75 80 Lys Gln Pro Thr Leu Ser Val Lys Lys Ile Thr GluLys Ser Thr Lys 85 90 95 Thr Gln Gly Ser Ala Pro Ala Pro Asp Asp Ala TyrPro Glu Ile Glu 100 105 110 Lys Phe Phe Pro Phe Asp Pro Leu Asp Phe GluSer Phe Asp Leu Pro 115 120 125 Glu Glu His Gln Ile Ser Leu Leu Pro LeuAsn Gly Val Pro Leu Met 130 135 140 Ile Leu Asn Glu Glu Arg Gly Leu GluLys Leu Leu His Leu Asp Pro 145 150 155 160 Pro Ser Pro Leu Gln Lys ProPhe Leu Pro Trp Glu Ser Asp Pro Leu 165 170 175 Pro Ser Pro Pro Ser AlaLeu Ser Ala Leu Asp Val Glu Leu Pro Pro 180 185 190 Val Cys Tyr Asp AlaAsp Ile 195 3 779 DNA Homo sapiens 3 atggccgcga gttgtggttt aaaccaggagtgccgcgcgt ccgttcaccg cggcctcaga 60 tgaatgcggc tgttaagacc tgcaataatccagaatggct actctgatct atgttgataa 120 ggaaaatgga gaaccaggca cccgtgtggttgctaaggat gggctgaagc tggggtctgg 180 accttcaatc aaagccttag atgggagatctcaagtttca acaccacgtt ttggcaaaac 240 gttcgatgcc ccaccagcct tacctaaagctactagaaag gctttgggaa ctgtcaacag 300 agctacagaa aagtctgtaa agaccaagggacccctcaaa caaaaacagc caagcttttc 360 tgccaaaaag atgactgaga agactgttaaagcaaaaagc tctgttcctg cctcagatga 420 tgcctatcca gaaatagaaa aattctttcccttcaatcct ctagactttg agagttttga 480 cctgcctgaa gagcaccaga ttgcgcacctccccttgagt ggagtgcctc tcatgatcct 540 tgacgaggag agagagcttg aaaagctgtttcagctgggc cccccttcac ctgtgaagat 600 gccctctcca ccatgggaat ccaatctgttgcagtctcct tcaagcattc tgtcgaccct 660 ggatgttgaa ttgccacctg tttgctgtgacatagatatt taaatttctt agtgcttcag 720 agtttgtgtg tatttgtatt aataaagcattctttaacag ataaaaaaaa aaaaaaaaa 779 4 202 PRT Homo sapiens 4 Met Ala ThrLeu Ile Tyr Val Asp Lys Glu Asn Gly Glu Pro Gly Thr 1 5 10 15 Arg ValVal Ala Lys Asp Gly Leu Lys Leu Gly Ser Gly Pro Ser Ile 20 25 30 Lys AlaLeu Asp Gly Arg Ser Gln Val Ser Thr Pro Arg Phe Gly Lys 35 40 45 Thr PheAsp Ala Pro Pro Ala Leu Pro Lys Ala Thr Arg Lys Ala Leu 50 55 60 Gly ThrVal Asn Arg Ala Thr Glu Lys Ser Val Lys Thr Lys Gly Pro 65 70 75 80 LeuLys Gln Lys Gln Pro Ser Phe Ser Ala Lys Lys Met Thr Glu Lys 85 90 95 ThrVal Lys Ala Lys Ser Ser Val Pro Ala Ser Asp Asp Ala Tyr Pro 100 105 110Glu Ile Glu Lys Phe Phe Pro Phe Asn Pro Leu Asp Phe Glu Ser Phe 115 120125 Asp Leu Pro Glu Glu His Gln Ile Ala His Leu Pro Leu Ser Gly Val 130135 140 Pro Leu Met Ile Leu Asp Glu Glu Arg Glu Leu Glu Lys Leu Phe Gln145 150 155 160 Leu Gly Pro Pro Ser Pro Val Lys Met Pro Ser Pro Pro TrpGlu Ser 165 170 175 Asn Leu Leu Gln Ser Pro Ser Ser Ile Leu Ser Thr LeuAsp Val Glu 180 185 190 Leu Pro Pro Val Cys Cys Asp Ile Asp Ile 195 2005 31 DNA Artificial Sequence Synthetic oligonucleotide. 5 gatgctctccgcactctggg aatccaatct g 31 6 32 DNA Artificial Sequence Syntheticoligonucleotide. 6 ttcacaagtt gaggggcgcc cagctgaaac ag 32 7 32 DNAArtificial Sequence Synthetic oligonucleotide specific to pCI-neoplasmid. vector. 7 ggctagagta cttaatacga ctcactatag gc 32 8 31 DNA Homosapiens 8 ctatgtcaca gcaaacaggt ggcaattcaa c 31 9 56 PRT Homo sapiens 9Met Ile Leu Asp Glu Glu Arg Glu Leu Glu Lys Leu Phe Gln Leu Gly 1 5 1015 Pro Pro Ser Pro Val Lys Met Pro Ser Pro Pro Trp Glu Ser Asn Leu 20 2530 Leu Gln Ser Pro Ser Ser Ile Leu Ser Thr Leu Asp Val Glu Leu Pro 35 4045 Pro Val Cys Cys Asp Ile Asp Ile 50 55 10 168 DNA Homo sapiens 10atgatccttg acgaggagag agagcttgaa aagctgtttc agctgggccc cccttcacct 60gtgaagatgc cctctccacc atgggaatcc aatctgttgc agtctccttc aagcattctg 120tcgaccctgg atgttgaatt gccacctgtt tgctgtgaca tagatatt 168 11 16 DNAArtificial Sequence Anchored primer sequence. 11 aagctttttt tttttg 16 1213 DNA Artificial Sequence Arbitrary primer sequence. 12 aagcttgctg ctc13 13 16 DNA Artificial Sequence n = a, g, or c; Anchored primersequence. 13 aagctttttt tttttn 16 14 194 PRT Mus musculus 14 Met Ala ThrLeu Ile Phe Val Asp Lys Asp Asn Glu Glu Pro Gly Arg 1 5 10 15 Arg LeuAla Ser Lys Asp Gly Leu Lys Leu Gly Thr Gly Val Lys Ala 20 25 30 Leu AspGly Lys Leu Gln Val Ser Thr Pro Arg Val Gly Lys Val Phe 35 40 45 Asn AlaPro Ala Val Pro Lys Ala Ser Arg Lys Ala Leu Gly Thr Val 50 55 60 Asn ArgVal Ala Glu Lys Pro Met Lys Thr Gly Lys Pro Leu Gln Pro 65 70 75 80 LysGln Pro Thr Leu Thr Gly Lys Lys Ile Thr Glu Lys Ser Thr Lys 85 90 95 ThrGln Ser Ser Val Pro Ala Pro Asp Asp Ala Tyr Pro Glu Ile Glu 100 105 110Lys Phe Phe Pro Phe Asn Pro Leu Asp Phe Asp Leu Pro Glu Glu His 115 120125 Gln Ile Ser Leu Leu Pro Leu Asn Gly Val Pro Leu Ile Thr Leu Asn 130135 140 Glu Glu Arg Gly Leu Glu Lys Leu Leu His Leu Gly Pro Pro Ser Pro145 150 155 160 Leu Lys Thr Pro Phe Leu Ser Trp Glu Ser Asp Pro Lys ProPro Ser 165 170 175 Ala Leu Ser Thr Leu Asp Val Glu Leu Pro Pro Val CysTyr Asp Ala 180 185 190 Asp Ile 15 945 DNA Mus musculus 15 tcttgaacttgttatgtagc aggaggccaa atttgagcat cctcttggct tctctttata 60 gcagagattgtaggctggag acagttttga tgggtgccaa cataaactga tttctgtaag 120 agttgagtgttttatgaccc tggcgtgcag atttaggatc tggattaagc ctgttgactt 180 ctccagctacttataaattt ttgtgcatag gtgccctggg taaagcttgg tctctgttac 240 tgcgtagtttttccagccgt ctcaatgcca atattcaggc tctctccctt agagtaatcc 300 agaatggctactcttatctt tgttgataag gataatgaag aacccggccg ccgtttggca 360 tctaaggatgggttgaagct gggcactggt gtcaaggcct tagatgggaa attgcaggtt 420 tcaacgcctcgagtcggcaa agtgttcaat gctccagccg tgcctaaagc cagcagaaag 480 gctttggggacagtcaacag agttgccgaa aagcctatga agactggcaa acccctccaa 540 ccaaaacagccgaccttgac tgggaaaaag atcaccgaga agtctactaa gacacaaagc 600 tctgttcctgctcctgatga tgcctaccca gaaatagaaa agttcttccc tttcaatcct 660 ctagattttgacctgcctga ggagcaccag atctcacttc tccccttgaa tggcgtgcct 720 ctcatcaccctgaatgaaga gagagggctg gagaagctgc tgcatctggg cccccctagc 780 cctctgaagacaccctttct atcatgggaa tctgatccgc tgtactctcc tcccagtgcc 840 ctctccactctggatgttga attgccgcct gtttgttacg atgcagatat ttaaacttct 900 tacttctttgtagtttctgt atgtatgttg tattaataaa gcatt 945 16 56 PRT Rattus rattus 16Met Ile Leu Asn Glu Glu Arg Gly Leu Glu Lys Leu Leu His Leu Asp 1 5 1015 Pro Pro Ser Pro Leu Gln Lys Pro Phe Leu Pro Trp Glu Ser Asp Pro 20 2530 Leu Pro Ser Pro Pro Ser Ala Leu Ser Ala Leu Asp Val Glu Leu Pro 35 4045 Pro Val Cys Tyr Asp Ala Asp Ile 50 55 17 56 PRT Mus musculus 17 IleThr Leu Asn Glu Glu Arg Gly Leu Glu Lys Leu Leu His Leu Gly 1 5 10 15Pro Pro Ser Pro Leu Lys Thr Pro Phe Leu Ser Trp Glu Ser Asp Pro 20 25 30Leu Tyr Ser Pro Pro Ser Ala Leu Ser Thr Leu Asp Val Glu Leu Pro 35 40 45Pro Val Cys Tyr Asp Ala Asp Ile 50 55 18 168 DNA Rattus rattus 18atgatcctga atgaagagag ggggcttgag aagctgctgc acctggaccc cccttcccct 60ctgcagaagc ccttcctacc gtgggaatct gatccgttgc cgtctcctcc cagcgccctc 120tccgctctgg atgttgaatt gccgcctgtt tgttacgatg cagatatt 168 19 168 DNA Musmusculus 19 atcaccctga atgaagagag agggctggag aagctgctgc atctgggcccccctagccct 60 ctgaagacac cctttctatc atgggaatct gatccgctgt actctcctcccagtgccctc 120 tccactctgg atgttgaatt gccgcctgtt tgttacgatg cagatatt 168

We claim:
 1. A method of inhibiting neoplastic cellular proliferationand/or transformation of a mammalian cell comprising: delivering to amammalian cell that overexpresses PTTG, a composition comprising a PTTGcarboxy-terminal-related polynucleotide that is antisense to: (A) (SEQID NO: 18); (B) a degenerate coding sequence of (A); or (C) apolynucleotide fragment of (A) or (B) that comprises a coding sequencethat encodes a proline-rich region; said PTTG carboxy-terminal-relatedpolynucleotide being complexed with a cellular uptake-enhancing agent,in an amount and under conditions sufficient to allow the polynucleotideto enter the cell, whereby expression of PTTG protein is prevented andneoplastic cellular proliferation and/or transformation of the cell isinhibited.
 2. The method of claim 1, wherein the cell is of humanorigin.
 3. The method of claim 1, wherein the cell exhibits neoplastic,hyperplastic, cytologically dysplastic, or premalignant cellular growthor proliferation.
 4. The method of claim 1, wherein the cell is amalignant cell.
 5. The method of claim 1, wherein the composition isdelivered to the cell in vitro.
 6. The method of claim 1, furthercomprising administering the composition to a mammalian subject, suchthat the composition is delivered to the cell in vivo.
 7. The method ofclaim 1, wherein the polynucleotide is a DNA or DNA analog.
 8. Themethod of claim 7, wherein the composition further comprises anexpression vector comprising a promoter, and the PTTGcarboxy-terminal-related polynucleotide is operatively linked to thepromoter in a transcriptional unit, such that transcription thereofresults in a transcript complementary to a 3′ coding region of a PTTG1mRNA or a fragment thereof.
 9. A composition, comprising a PTTGcarboxy-terminal-related polynucleotide having a polynucleotide sequenceantisense to: (A) (SEQ ID NO:18); (B) a degenerate coding sequence of(A); or (C) a polynucleotide fragment of (A) or (B) that comprises acoding sequence that encodes a proline-rich region.
 10. The compositionof claim 9, further comprising a pharmaceutically acceptable carrier.11. The composition of claim 9, further comprising a cellularuptake-enhancing agent complexed with said PTTG carboxy-terminalpeptide.
 12. The composition of claim 11, wherein said uptake enhancingagent comprises a lipid agent.
 13. The composition of claim 11, whereinsaid uptake enhancing agent comprises a polycationic lipid agent. 14.The composition of claim 11, wherein said uptake enhancing agentcomprises a cellular uptake-enhancing and/or importation-competentpeptide segment.
 15. The composition of claim 9, wherein thepolynucleotide is a DNA or DNA analog.
 16. The composition of claim 15,further comprising an expression vector comprising the the DNA and apromoter in a transcriptional unit, wherein the PTTGcarboxy-tcrminal-related polynucleotide is operably linked to thepromoter in an antisense orientation.
 17. A kit for the treatment ofneoplastic cellular proliferation, said kit comprising: the compositionof claim 9; and instructions for the use of said composition forinhibiting neoplastic cellular proliferation and/or transformation.